WASHINGTON (AP) -- The Federal Trade Commission is warning consumers who want to help the victims of this week's Oklahoma tornado that they need to be wary of scams and make sure that their donations are going to a reputable organization.

In the wake of major disasters, legitimate charities often face competition from scammers who either collect for fake charities or aren't truthful about how their group will use donations, the FTC said.

The FTC recommends that consumers donate to charities that they know and trust, and be wary of groups that appear to have sprung up overnight in connection with a specific disaster.

Consumers should also ask fundraisers whether they are being paid, who they work for, and what percentage of donations actually goes to the charity. If the answer is unclear or doesn't meet expectations, consider donating to another group, the FTC said.

The FTC also warned against giving out personal or financial information unless it's clear that the charity is legitimate. In addition, consumers should never send cash, because there isn't a way to be sure that the charity actually received the money and there won't be a record of the donation for tax purposes.

Consumers can check out charities through organizations such as the Better Business Bureau's Wise Giving Alliance, Charity Navigator, Charity Watch, and GuideStar.

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