Jailed Philippine politician Leila de Lima was briefly taken hostage during an attempted breakout at a prison in the Manila capital region, police said Sunday.

De Lima, a former senator and outspoken critic of former President Rodrigo Duterte, has been held at the national police headquarters for more than five years along with other high-profile detainees. She is due to appear in court on Monday. 

"They saw her as an ideal cover. Their intention really was to escape," police chief General Rodolfo Azurin told local radio station DZBB, adding that she was not the target of the attack. 

After the incident, Philippine President Ferdinand Marcos Jr. tweeted saying he would ask de Lima if she wishes to be transferred to another facility. 

What happened during the attempted breakout?

Three inmates staged a rampage at the prison in an attempt to escape. One police officer was stabbed with an improvised knife. Another officer shot two of the inmates dead.

The third prisoner ran to de Lima's cell and held her hostage before being shot dead as well, the police said. 

The three inmates were reportedly members of the militant group Abu Sayyaf, which has been accused of kidnapping and beheading several foreigners.

De Lima was unhurt, and the situation in the prison was under control, authorities said. An investigation is being carried out. 

"She was brought to the hospital for the standard medical check-up. But based on the information given to us by our staff who's with the senator now, she appears OK," said de Lima's lawyer Boni Tacardon.

Since Marcos Jr. took over the presidency this June, rights groups and diplomats have renewed calls for de Lima's release. 

De Lima had spent a decade investigating "death squad" killings during Duterte's early days as Davao city mayor, and in his early days as president. She was elected as senator in the 2016 elections and became a leading opposition voice. 

She was arrested in February 2017 after being accused of running a drug trafficking ring. 

tg/wd (AFP, AP)