A guy named <removed> is a scamer http://steamcommunity.com/id/<removed>

[Morten]

http://steamcommunity.com/id/<removed> its a scamer he scamed me on a awp boom field tested and a P2000 | Grassland Leaves field tested and when i pressed ready to trade he took away his awp i was suppost to trade with him and he ignore me now and have take me away from friends

[Legitti]

http://steamcommunity.com/sharedfiles/filedetails/?id=177244559

[WhereIsBusmin]

Report suspected scammers via their profile: "More" > "Report Violation".

Also, we don't name and shame here so you may want to remove his name and profile info from your post.

Additional information: Steam Support > Steam Trading Policy

What is Steam's policy on returning scammed items/gifts?

Steam will not return any items or gifts that you feel have been traded unfairly. There are no exceptions to this policy. All trades are final. If you were scammed, you may report this scam to Steam Support so that action may be taken against the scammer. This does not include fraudulently purchased games that you receive. Please see this question for more information on what we do to handle fraudulent purchases.

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Why will Steam not return items that were scammed?

During the trade process, Steam asks you to confirm your trade multiple times. It is your responsibility to review the items that you are trading. You first confirm the trade by checking the box that states, "Check this box when ready to trade". Once checked, you cannot add any items to the trade. If you remove an item you will have to re-check the box to confirm that you are ready. Once both users in the trade have checked this box, the final confirmation button will turn green. Both users must click this button to complete the trade. A log of the trade is also kept in a separate chat box within the trade window.