Big Island police yesterday arrested a Puna man as a suspect in the vehicular tragedy in which two Hilo women were killed Sunday morning and a third — the alleged assailant's ex-girlfriend — injured on the Mamalahoa Highway between Kona and Waimea.

Police said Vernon E. Costa intentionally hit the women's compact car with his truck, forcing it off the road.

Costa, 41, who has a criminal record, was arrested at about 4 p.m. yesterday, after he was found hiding in bushes in the Eden Roc subdivision of Puna, more than 60 miles from the scene of the accident.

He was booked for investigation of first-degree murder, two counts of second-degree murder and one count of attempted second-degree murder.

Police described a chilling scenario: A silver truck with a lone male driver and a gold sedan with three panicked women speeding through the night at tight quarters. A woman in the compact car repeatedly calling police by cell phone to say that they were being tormented by a man in a truck.

They were driving the dark Mamalahoa Highway shortly after midnight, heading uphill, from Kona toward Waimea. The calls from the sedan indicated the car was being chased.

The truck hits the car, causing it to veer off the highway. It rolls over on rugged lava, ejecting and killing two women and leaving the other injured inside the wreckage. The truck also crashes, its driver walking away from the scene.

Police initially characterized the case as one of "road rage," but learned that one or more of the women knew their assailant, and that he knew who he was chasing.

Killed were Pua Lei Santa-Isabel, 26, and Casey Ann Swain, 35, both of Hilo. Preliminary indications are that they were effectively bystanders in a dispute between the two survivors of the wreck.

The car's lone survivor was described as a 19-year-old Hilo woman, who was sitting in the front passenger seat and was making the phone calls to police.

"Detectives have learned that Costa and the 19-year-old woman had a prior relationship that ended about six months ago," a police press release said. "Police have confirmed that there was a history of abuse in the relationship and that there had been a temporary restraining order, which had expired, filed."

In February, Costa was named in a temporary restraining order brought by Janelle Nardin of Hilo. The restraining order, filed Feb. 24, was dissolved two weeks later, on March 7.

Early Sunday morning, just minutes after midnight, police dispatchers sent officers to the area between Hu'ehu'e Ranch and Pu'uanahulu as the first calls came in. The caller reported the two vehicles were passing the 23-mile-marker at 12:11 a.m.

Two more calls and seven miles later, the derby between the truck and the compact car ended. A passerby called police to report that two vehicles had been involved in an accident at the 16-mile marker, near Pu'uanahulu.

Two women's bodies lay on the rough lava. A passing driver picked up the third woman and took her to North Hawai'i Community Hospital in Waimea. She was treated for undisclosed injuries and released. The pickup truck's driver, who police said they believed to be Costa, had disappeared. Police launched an islandwide search for him.

The vehicles had gone off opposite sides of the road.

The silver-gray 1998 Dodge Dakota pickup truck had some damage to one side, and had two flat tires as it sat on the lava on the makai side of the highway with severe damage to its undercarriage, said police Maj. John Dawrs. The truck was not registered to Costa. Police said it had been borrowed, but did not identify the owner.

The other car, a gold 1987 Honda Civic, ran off the right, mauka side of the road. It hit the lava and rolled. Dawrs said the small car's roof was crushed and its body severely damaged.

"It's a wonder anyone survived," he said. "That section is very unforgiving. Once you go off the shoulder a little bit, you're already in trouble."

Police closed Mamalahoa Highway from 12:30 to 7:15 a.m. as they investigated the incident.

Costa has twice been charged with abuse of a member of his family or household, the most recent case still ongoing in the courts. Women have sought temporary restraining orders against him, including the one this year filed by Nardin. He has also been charged with assault and escape.

In 2002, Costa was convicted of drunken driving. His driver's license was suspended for 90 days. Costa was found guilty three times during the past decade — in 1996, 1997 and 1999 — of driving without a valid license.

Reach Jan TenBruggencate at jant@honoluluadvertiser.com.