Maryland and Howard County police were investigating yesterday how a Columbia man accused of fatally shooting his estranged wife and wounding her daughter obtained a banned gun that was not registered in the state.

Police said Tuse S. Liu, 49, used a Jennings .380 semiautomatic handgun -- considered a Saturday night special in Maryland -- in the shootings Thursday outside the Howard County Circuit Courthouse. So Shan Chan, 52, was killed and Wing Sau Wu, 26, of Baltimore was critically wounded.

"There is no record of [Liu] purchasing a regulated firearm in the state of Maryland," said Capt. Tom Bowers of the state police.

Pub Date: 3/17/99