A man suspected of planning to attack a Missouri hospital was killed during a shootout with F.B.I. agents, the authorities said on Wednesday.

The deadly encounter took place on Tuesday afternoon in suburban Belton, Mo., after agents on a tactical team tried to arrest the man as part of a domestic terrorism investigation.

It was not clear whether the man was killed by F.B.I. agents or died by suicide. He was taken to a hospital, where he was pronounced dead. Officials identified the man as Timothy R. Wilson, 36.

According to officials, Mr. Wilson had expressed racist and anti-government sentiments. He had been under F.B.I. scrutiny since September, and the authorities said that at one point he had considered attacking multiple targets, including a school with a large number of black students, as well as a mosque and a synagogue.