BUENA PARK  (AP) — A man shot and wounded by SWAT officers after a standoff at a Southern California bank was armed with a sawed-off shotgun and several homemade pipe bombs, and he knew the bank manager he held hostage, police said Friday.

"They had a business transaction that probably is the impetus that led to the event," Buena Park Police Chief Corey Sianez told the Orange County Register.

Sianez said he could give no further details on the pair's dealings. Police had previously characterized the standoff as a robbery gone bad.

The suspect, Myung Jae Kim, 55, remained in the intensive care unit at University of California, Irvine Medical Center on Friday.

During Thursday's four-hour standoff, Kim let the other half-dozen people in the bank go but held on to the female hostage and demanded money.

"He wasn't going to let the bank manager go," police Sgt. Roger Powell told the Register. "He was determined to get $250,000, or he was going to kill her and himself."

The SWAT team approached the front of the bank under the pretense of bringing food for the hostage when the shootout began, Powell said.

Video from a television helicopter showed at least eight officers with guns drawn approaching the bank in a small strip mall when the front window shattered. The woman was pulled from inside the shattered doors.

Kim fired his sawed-off shotgun once, and his shrapnel hit three officers, leaving them with minor injuries on their arms, Powell said.

Several SWAT team members fired back and Kim was hit multiple times, he said.

In the aftermath, officers found a homemade pipe bomb in Kim's pocket and three more around the bank.

"It was a guy who showed up with a plan that could have gone really bad," Powell said. "It was going to go real ugly if they hadn't intervened."

The hostage, whose name was not released, was not injured.