A former Waikoloa hotel worker who shot and killed his wife's longtime lover was found guilty Wednesday of second-degree murder.

A Big Island jury also found Lito Mateo guilty of using a firearm in the commission of a separate felony. Mateo shot 38-year-old Tito Rafol 18 times with a .45-caliber semiautomatic handgun in the parking lot of the Waikoloa Beach Marriott Resort & Spa on March 8, 2007.

Mateo, 56, will face a mandatory life sentence on the murder charge and could receive an additional 20 years imprisonment on the firearms charge. He's to be sentenced Feb. 4 by Hilo Circuit Judge Glenn Hara.

The jury, which was instructed to return Monday morning, will decide if the murder was committed in an especially "heinous, atrocious or cruel" manner, as prosecutors allege. If the panel finds that to be the case, Mateo could receive a life sentence without the possibility of parole.

Numerous people, including Mateo's wife and Rafol's sister, witnessed the shooting, which occurred during the shift change at around 4 p.m.

Mateo, a Filipino immigrant and a naturalized U.S. citizen, worked two full-time jobs. He was a landscaper by day and a steward in the Marriott's kitchen at night.

Rafol and Mateo's wife both worked in the Marriott's housekeeping department. Cornelia Mateo testified during the trial that she and Rafol had an affair that started in 1999.

Testimony in the trial established that the Mateos' daughter, Dina, had heard gossip about the affair since she was a student at Honoka'a High School. The couple's oldest son, Henry, 28, a cook at the Marriott, had heard about it for at least two years.

Two psychologists and a psychiatrist testified that Mateo was distressed not only by his wife's infidelity, but also by Rafol's calling him "pukol," a derogatory Ilocano word meaning "cripple."

Mateo was born with deformed hands.