The death of TV actress Nida "Tangmo" Patcharaveerapong appears to be an accident based on the evidence, according to police, who have not finished collecting evidence.

The national police chief made the statement a couple of days before the results of forensic examination will be known.

The body of the 37-year-old actress was recovered on Feb 26 almost two days after she fell into the Chao Phraya River while on a speedboat with five others.

The boat's owner and the driver were charged with operating an unlicensed vessel and negligence leading to death. The other three on board were Tangmo's manager and two others.

It was reported that the five were summonsed for questioning on Sunday. They have been fiercely criticised by netizens over the incident with Tangmo's mother also involved in a row over compensation for her daughter's death.

The boat owner recently offered Tangmo's mother 30 million baht in compensation.

At least 29 witnesses have now been questioned about the actress' death.

Police said on Sunday that they are still collecting evidence and the investigation will take some time.

Divers from the marine police division on Sunday recovered two objects from the Chao Phraya River near Phibul Songkhram pier and handed them over to forensic examination. It was believed that police were looking for objects that the witnesses claimed to have tossed into the river after Nida fell off the speedboat.