MANTLE RESOURCES INC.

FOR IMMEDIATE RELEASE

Thursday, June 5, 2008

(No.2008-06-17)

Contact:

Investor Relations

Phone (604) 684-2181

info@mantleresources.com

MANTLE RECEIVES INITIAL NI 43-101 INFERRED MINERAL RESOURCE ESTIMATE REPORT FOR THE CARDIAC CREEK DEPOSIT

Vancouver, B.C. � June 5, 2008 � Mantle Resources Inc. (TSX Venture: MTS; Frankfurt: AOF7E1) (the �Company�) is very pleased to announce the filing of the NI 43-101 compliant technical report entitled �Geology, Diamond Drilling and Preliminary Resource Estimation, Akie Zinc-Lead-Silver Property, Northeast British Columbia, Canada�.� This report on the Company�s wholly owned Akie property, authored by D.G. MacIntyre, P.Eng., and R.C.Sim, P.Geo., documents the work conducted by Mantle over the past 2 � years and describes the methods used to generate the previously announced resource estimate (see April 16, 2008 news release). This resource estimate follows diamond drill programs carried out by the Company during the period September 2005 to November 2007 and establishes the Cardiac Creek deposit as one of the premier base metal projects in Canada. The resources are summarized below.

Cardiac Creek Deposit Mineral Resource

The Cardiac Creek deposit inferred mineral resource -- at a series of zinc cut-off grades (2% to 7%) -- is provided in the table below.� The 23.595 million tonnes at a zinc cut-off grade of 5% contains 3.95 billion lbs of zinc, 0.78 billion lbs of lead and 8.95 million oz of silver.

Cardiac Creek Deposit Inferred Mineral Resource

������������������������������������������������������������� �������������Notes��������������������� �Base Case� cut off grade of 5.0% Zn highlighted in table

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Cardiac Creek Deposit

The Cardiac Creek deposit occurs within a planar, steeply-dipping (-70^o), sheet-like zone of semi-massive to massive sulphides comprised of varying amounts of pyrite, sphalerite and galena (+/- barite) which has been traced over strike length of 6.5 kilometres and a downdip extent in excess of 800 metres. This mineralized zone ranges in thickness to as much as 40 metres. At the 5% zinc cut-off limit, the deposit

has an approximate 900 metre strike length and a dip length of 750 metres and has an average true thickness of 10.8 metres in the area of potential economic interest.

There are a total of 56 drill holes on the property with a total core length of 26,957 metres.� Of these, 48 holes are within the proximity of the resource model and utilized in the resource estimate.� The remaining 8 drill holes test the mineralized horizon over a total strike length of +6.50 kilometres.

Mineral Resource Estimate Criteria

Resources are limited within a planar zone of mineralization (Minzone) interpreted from drill hole assay sample data coupled with the understanding of the local geologic features observed on the property. Grade estimates for zinc, lead and silver are made using ordinary kriging with a nominal block size of 5x10x5 metres. Potentially anomalous (outlier) sample grades have been identified through statistical evaluation and limits appropriately applied during interpolation.� Bulk densities have been estimated in the block model from drill core measurements, using the inverse distance squared interpolation method.� Inferred mineral resources are limited to a maximum of 125 metres from a drill hole.

Highlights and Recommendations of the Report

The report notes that the resources outlined at the 5.0% Zn cut-off level are considered reasonable based on assumptions derived from operations with similar characteristics, scale and location. The report further states that the resource occurs as a relatively continuous zone which is favourable with respect to selectivity and other factors when considering mining options.� This, when combined with the results of previous geological, metal zoning and structural investigations, and the results of drilling completed to date, suggest that the Cardiac Creek deposit has economic potential sufficient to warrant additional expenditures on exploration and development.

The report recommends a 14 hole, 7,000 metre drilling program be completed to infill the current base case resource (>5% zinc) to approximately 100 metre intervals, allowing the present inferred resource to be elevated to the indicated category, and to provide information on continuity of the Cardiac Creek zone mineralization which would be necessary in order to design a future underground exploration program.� Along with the drilling program, continued metallurgical testing and environmental base line studies are also recommended, for a total estimated cost of $6,187,500.

Additional work beyond that recommended in the report is expected to include drilling updip and on strike to ascertain the limits of the deposit for longer term planning purposes.� There are additional prospective exploration targets on the property that are also planned to be drilled.

Mobilization activities for the drill program have commenced and drilling is expected to be underway by mid-June.� Field activities related to environmental base line studies and mapping are currently in progress.

J.W. Mustard, President of Mantle, states �We are extremely pleased with the initial mineral resource estimate of the Cardiac Creek deposit.� The receipt and filing of this report is a key achievement for the Company and benchmarks the Akie property, and the district, for its significant value and exploration potential.� The recommended exploration work program this year will be focused on providing the additional building blocks to advance the deposit.� Our 2008 program at Akie will continue to establish the Cardiac Creek Deposit as one of the best base metal deposits being explored in Canada today.�

About the Akie Property

The Akie zinc-lead property is situated within the southern-most part (Kechika Trough) of the regionally extensive Paleozoic Selwyn Basin, one of the most prolific sedimentary basins in the world for the occurrence of SEDEX zinc-lead-silver and stratiform barite deposits. 

Drilling on the Akie property by Inmet Mining Corporation during the period 1994 to 1996 and by Mantle in 2005, 2006 and 2007 has identified a significant body of baritic-zinc-lead SEDEX mineralization (Cardiac Creek deposit).� The deposit is hosted by variably siliceous, fine grained clastic rocks of the Middle to Late Devonian �Gunsteel� formation.

Two similar deposits, Cirque and South Cirque, located some 20 km northwest of Akie and owned under a joint venture by Teck Cominco and Korea Zinc, are also hosted by Gunsteel rocks and have a combined geologic inventory in excess of 50 million tonnes.

Qualified Person

Independent consultant Robert C. Sim, P.Geo., a Qualified Person as defined by National Instrument (NI) 43-101, is responsible for the mineral resource estimate summarized in this release.

John R. Fraser, P.Geo. (B.C.), Vice President of Exploration and a Director of Mantle Resources, is the Qualified Person for the Company, as defined by NI 43-101, and is responsible for the technical information contained in this release.

Note

• Mineral resources reported in this release have been calculated as of April 11, 2008 in accordance with the standards of the Canadian Institute of Mining and Metallurgy (December 11, 2005) and National Instrument (NI) 43-101. U.S. investors should be aware that the SEC in the United States does not recognize these terms.
• It cannot be assumed that all or any part of an Inferred Resource will be upgraded to a higher category of Mineral Resource.
• There are no known factors related to environmental, permitting, legal, taxation, socio-economic, marketing or political issues which could materially affect the mineral resource presented in this release.

The TSX Venture Exchange has neither approved nor disapproved the contents of this press release.

ON BEHALF OF THE BOARD OF DIRECTORS

MANTLE RESOURCES INC.

�PEEYUSH VARSHNEY�

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pEEYUSH vARSHNEY, LL.B

CEO

CAUTION REGARDING FORWARD LOOKING STATEMENTS: This release includes certain statements that may be deemed �forward looking statements�. All statements in this release, other than statements of historical facts that address historical fact, including, without limitation, statements regarding future plans and objectives of Mantle,� are forward-looking statements that involve various risks and uncertainties. There can be no assurance that such statements will prove accurate and actual results and future events may differ materially from those anticipated in such statements. Important factors that could cause actual results to differ materially from Mantle�s expectations are detailed herein and from time to time as filed with securities regulators.