An internet security site is warning of cyber-scammers using the Haiti quake to steal money.
On a message posted on its website, Symantec says it is already seeing spam emails soliciting donations, using real addresses and the names of aid agencies.
The emails ask for donations to be made via Western Union money transfer.
Oxfam says people should check phone numbers and websites to make sure they are legitimate.
Communications director Prue Smith says aid agencies usually send emails only to existing supporters, so people should be wary if they get one from an aid agency they have not heard from before.