A US official said this week that Obama could participate in an Asean summit to be hosted in Cambodia in November.
Witnesses said security guards for the TTY Company opened fire with AK-47s.
Escapees climbed over the walls or jumped the metal gates of the Prey Speu Social Affairs Center Wednesday in full view of observers.
Cambodian police in Kampong Speu province discovered five bodies thought to be those of Frenchman and his four children. Police are investigating how they were ended up in a car dumped in a pond behind the family home.
This comes a day after defense attorneys say they want to summon the head of a leading genocide research organization before the court.
In her letter to the court, shared with reporters, she said she had paid the fine in full, from reductions in her parliamentary salary.
Asean countries are facing a multitude of issues which includes a dispute over the South China Sea.
The Documentation Center has provided around 500,000 documents to the tribunal since its inception.
Meanwhile, the US is making diplomatic efforts to improve its relationship in Cambodia.
Thirty-eight people remain in unlawful detention after they were seized by authorities as they protested outside City Hall this week.
Hor Namhong told reporters Thursday that Asean leaders could help ministers of North and South Korea meet on the sidelines.
Jailed Khmer Rouge leader Khieu Samphan refused to answer questions from the UN-backed tribunal on Thursday.