hree prisoners including two Saudi Arabian nationals were killed in a fight in a jail in India's remote northeastern state of Manipur, officials said.

A police spokesman said the incident took place just before dawn at the Manipur central jail in the state capital Imphal.

“Two Saudi prisoners attacked and killed another inmate lodged in the same cell, and on hearing about the incident other inmates counter-attacked and killed the two foreign jail inmates,” P. Doungel, the state's additional director general of police told reporters.

The two Saudi nationals — Sushak Yusuf Ahmed and Abdul Salam — were facing trial on charges of entering the country without valid travel documents after being arrested in 2013.

The other deceased inmate has been identified as Thangmilian Zou, a local tribal member from Manipur's Churachandpur district.

Doungel said it was not immediately clear what triggered the fight.

“Autopsy of the three is being done. We are investigating the incident and trying to find out if any crude implements were used by the inmates in the attack,” Doungel said.

At least two prison guards and one official were also injured when they tried to intervene and stop the fight.

The Saudi government has sought a report from the Indian home ministry about the deaths of its nationals, police sources said.

Manipur, which borders Myanmar, has long been mired in separatist violence, with some 20 rebel groups fighting for greater autonomy or secession from India.