A 14-year-old student is suspected of killing his grandparents at home. He then opened fire at a high school in Nonthaburi near Bangkok on Friday.

Police said the killings at home happened before the school attack. Reports differ on how many died in the school shooting.

Police said at least six people were killed and others were hurt. Another report said at least eight people died.

Some reports said the death count was still changing. Police said the gun belonged to the student's grandfather.

The teenager fired 26 rounds during the attack. He was found with another 34 rounds of ammunition.

He died by suicide after the attack. No motive has been found so far.