– It was an important Buddhist holiday, so the back gate to the forest temple was open. And it was the perfect place for an ambush.

A Thai soldier who had already killed three people drove a stolen military Humvee to the temple grounds and parked inside the gate, partly hidden by trees. Two monks who were raking leaves saw him but assumed he was there for some military purpose.

The soldier's deadly rampage Saturday had started as revenge against specific people he thought had wronged him. But at the temple, Wat Pa Sattharuam, it turned into something much bigger. It was here that he began gunning down random strangers, including children.

All told, Sgt. Major Jakrapanth Thomma killed 29 people and wounded 58, most of them in a shopping mall that he went to after the temple, leaving Thailand in shock and mourning. Unable to shake the images in their minds, survivors ask what could have motivated him and wonder why they were victimized or why they were spared.

"As he loaded his gun, he looked at me," said one of two monks, Phra Pom Surasokkako, who witnessed much of the bloodshed. "If he wanted, he could have shot me and stopped me from calling the police."

On Tuesday, the chief of Thailand's army, Gen. Apirat Kongsompong, apologized for the mass shooting, describing it as "sathuen khwan," an event that shocks the spirit.

He acknowledged that, as had been reported, the sergeant major was initially motivated by a financial dispute with his superior officer's family. But, he said, "the second that the perpetrator pulled the trigger and killed, in that minute he is a criminal and no longer a soldier."

The army chief said there would be an investigation into a business operated by the superior officer, a colonel, and his family, arranging house purchases and home loans for soldiers, and whether other high-ranking officers were involved. The gunman had told friends that the colonel's family had refused to pay money they owed him from such a deal.

Stole the Humvee

At a meeting Saturday, the sergeant major shot and killed the colonel and his mother-in-law, and wounded a property agent. Then he stole the Humvee and went to an armory, killed a soldier guarding it, and stole weapons and ammunition.

So far, there has been no indication of why Jakrapanth drove to the temple, a wooded monastery established to give monks peace and solitude away from the troubles of modern life, and turned his lethal rage on the people there.

As the two raking monks watched from a distance, the sergeant major began loading ammunition into weapons. He took his time and kept careful watch on his surroundings.

"He didn't panic," said one of the monks, Phra Manasawin Teeranguro.

Pom shot a video of the gunman from about 50 yards away. The sergeant major fired 10 rounds in the other direction, and the monk bolted, capturing his own running shadow on video.

The gunman kept shooting at targets outside the temple gate, spraying cars, buildings and people with bullets.

Within the temple grounds, the first to die was a pharmacist who drove by in a bronze sedan, heading toward the exit. The sergeant shot her as she passed by, and her car crashed into a tree. Her son, riding with her, was injured.

The next victim was a 13-year-old boy on a motorbike who also was driving toward the gate. The gunman waited until the boy was almost next to him and then shot him several times, Pom said. As the boy lay on the ground, he shot him in the head.

By this time, Pom, 33, had called police, and Manasawin, 24, had run to the front gate to try to stop other cars from entering the grounds. But vehicles kept coming.

A police car arrived, siren blaring, and drove up to the back gate. The gunman was lying in wait and killed both occupants, a police officer and a police volunteer, before they could get out of the car.

An SUV approached, and Pom screamed as loudly as he could for the vehicle to stop, but it drove past.

The sergeant major stood in the middle of the road. The SUV screeched to a halt, and he fired through the windshield. He shot out a tire and then opened the doors, shooting the driver and his four passengers in turn at point-blank range. Only one survived.

Outside the back gate, Thirawat Watchareesawin, 14, was riding in a car with a friend toward the temple entrance when he saw a sedan, a motorcycle and a police car stopped by the side of the road. Then he saw the gunman pointing his weapon at them.

"I saw him looking at my driver pointing his gun to his head," he said. "I yelled right away, 'He is going to shoot you!' "

His friend reversed the car quickly and ordered him to duck as bullets ripped through the vehicle, wounding both of them. The 14-year-old suffered bullet wounds in both legs, and the driver was shot twice in the arm.

Jakrapanth drove to the Terminal 21 mall, which was packed with people on the holiday, and continued his shooting spree, killing 16 people there before police finally shot him dead the next morning.