Detectives are stepping up their hunt for brazen robbers who have hit several banks in Union and Middlesex counties.

The FBI announced Monday it is offering a $35,000 reward for information leading to the suspects? arrests. Investigators have had a hard time finding the two armed robbers because they were wearing masks and wigs. Detectives say with each robbery, the two get more aggressive.

?These individuals typically will enter a bank and order the bank customers and bank employees to [hit] the floor,? FBI agent Weysan Dun said. ?They?ve become increasingly forceful and in some cases they have violently accosted employees or customers.?

Since January, the robbers have held up nine banks in East Brunswick, Edison, Metuchen, Rahway and Woodbridge.

Anyone with information should call the FBI at (973) 792-3000.

For a press conference with Dun on the robberies, go to channel 612 on your iO digital cable box and select iO extra.