Sucheep Sornsung, 41, came home from the party and started to quarrel with his family before the shootings, the police said. The incident took place in Thailand's southern Chumphon province.

The victims included his 6-year-old daughter and a 9-year-old, as well as two men and two women aged between 47 and 71, who were family members of Sucheep's wife, who survived. One man was injured and survived the shooting.

"The (suspect) went to a party with his friends then came home to see his wife's family and they started arguing before he used his gun to shoot them," Police Major General Saharat Saksilapachai, commander of Chumphon provincial police, told Reuters.

"According to witnesses, the man did not drink a lot and we suspect that his rage came from old problems with his wife's family," Saharat said.

The police said Sucheep had a drug-related criminal record and had previously been jailed but there was no history of violence against his family.

Thailand has a high rate of gun ownership and gun-related death, but mass shootings are rare.

According to 2016 data from the University of Washington, Thailand had the highest reported rate of gun-related deaths out of 10 countries in Asia. It was about 50 percent higher than the Philippines, which was second on the list.

According to Thailand's Interior Ministry, there are more than 6 million registered firearms in the country of 69 million people. But there are also many unregistered guns in circulation.

REUTERS