FEMA will replace locks on as many as 118,000 trailers used by Gulf Coast hurricane victims after discovering that the same key could open multiple mobile homes, the agency said Monday.

Some keys could open as many as 50 different locks — causing a security risk in heavily populated trailer parks in Louisiana and Mississippi.

"We're aggressively stepping out to minimize the risk," said Federal Emergency Management Agency spokesman Pat Philbin. He said FEMA worked though the weekend after discovering the problem last Friday at a Baton Rouge, La., trailer park that has hurricane victims.

It is unknown how many trailers will need to have their locks replaced, Philbin said.

In all, FEMA has issued about 150,000 travel trailers and mobile homes to evacuees since hurricanes Katrina and Rita slammed into the Gulf Coast last year. But about 32,000 have been taken out of service, Philbin said.

The snafu stems from a limited number of lock makers — three — that trailer manufacturers use when building mobile homes, FEMA officials said. That increases the likelihood of locks being the same, they said.

FEMA bought 13 different kinds of travel trailers for hurricane evacuees, the officials said.