Thai police charged an Australian man on Thursday with recklessly causing the death of his girlfriend when two jetskis they were riding on smashed into each other.
Emily Jayne Collie, a 20-year-old Australian, died Sunday in a horrific collision off the coast of Phuket island.
Her boyfriend Thomas Keating, also in his twenties, was on the other jetski.
On Thursday police charged Keating under Section 291 of Thailand's criminal code.
"He was formally charged this morning with reckless action that results in the death of another person," Colonel Sanya Thongsawad, commander of Karon Police station in Phuket, told AFP.
"Police are questioning him this afternoon to see whether he will confess or deny the charge," he added.
Keating faces up to 10 years in jail if convicted although a confession could result in a suspended sentence, Sanya said.
The decision by Thai police to charge Keating comes after Collie's parents said they did not blame him for their daughter's death.
"This was a tragic accident. We do not believe anyone was at fault. In particular, we do not place any blame on Tom Keating, who we care about very much and we know loved Emily deeply," the parents said in a statement released through the Department of Foreign Affairs and Trade, according to Australian media.
Australian media said Keating may not have seen his girlfriend's jetski because of strong sunlight reflecting off the sea.
But investigators said the couple were driving dangerously before the collision.
"It seems that they were having too much fun, driving in a zigzag to splash water at each other," Sanya told AFP, noting the jetskis both suffered damage to their left flanks, which suggested a near head-on collision.
Keating penned an emotional tribute to his girlfriend after the crash on Facebook.
"I'm so broken and I know I'll never never be able to mend," he wrote, adding: "I wish I could just bring you back into my arms."