The convicted felon accused of beating a woman to death with the butt of a shotgun on a suburban Kailua street was charged with second-degree murder yesterday and ordered held on $1 million bail.

Alapeti Siuanu Tunoa Jr., 30, was also charged with five other felony counts stemming from the brutal assault that left his former girlfriend dead and a bystander who tried to help her seriously injured, prosecutors said.

Tunoa was arrested Wednesday after fleeing the scene of the killing, in which he allegedly rammed the car of 29-year-old Janel Tupuola with his SUV, then struck her repeatedly with the butt end of the rifle-type shotgun, swinging it like an axe, according to police statements.

Other charges filed against Tunoa last night included first-degree terroristic threatening, first-degree assault and using a firearm in the commission of a felony, prosecutors said.

Tupuola had no pulse when the first off-duty police officer arrived on the scene, the police affidavit said. She was taken to Castle Medical Center, where she died.

The attack was witnessed by several people, including an elderly man who tried to come to Tupuola's aid.

When the man approached the altercation, Tunoa pointed the shotgun at him and said, "Mind your own business, old man, before I hurt you," according to a police affidavit. When the man grabbed Tunoa's arm, he struck him with the shotgun, causing "life-threatening injuries," the affidavit said.

Tunoa drove away in a Ford Explorer. Police said an anonymous caller first spotted Tunoa, described as a 340-pound man wearing a yellow shirt and black pants, running into properties near Likeke Place in Kane'ohe.

He was found inside a home. Tunoa, drenched in sweat, was arrested and subsequently identified as the killer by four people who witnessed the Kailua attack, police said.

Reach Mike Leidemann at mleidemann@honoluluadvertiser.com.