Former Philippine leader Rodrigo Duterte has suggested killing senators in a bomb blast to make room in the Senate for his preferred opposition candidates, as his word war with incumbent President Ferdinand Marcos Jr heats up amid a midterm election campaign.

The ex-president made the comments on Thursday night during a speech at a rally in Manila endorsing nine opposition senatorial candidates running in the May national elections.

?There?s many of them [senators]. So what should we do? Let?s just kill the senators now so we will have more vacancies,? Duterte said in a mix of Filipino and English, drawing loud cheers from the crowd.

?If we can kill about 15 senators, then we can all get into the Senate. That would be a pity though. Some of them are really annoying. But not all,? added Duterte, who is running for Davao mayor, a position he held for two decades before becoming president.

?Talking about opportunities, the only way to do it is to use a bomb,? Duterte added, evoking memories of the deadly 1971 bombing at a campaign rally, which left nine people dead and scores wounded, including six incumbent and future senators as well as the mayor of Manila.

Duterte?s statement followed the impeachment of his daughter, Vice President Sara Duterte, whose political fate, including possible removal and perpetual disqualification from public office, will be decided by the 24-member Philippine Senate.

The trial date of the younger Duterte has not yet been set, but it is likely to happen after the May polls. With two-thirds of the number of senators required to convict, the final composition of the Senate could prove critical for her political survival. The majority of the senators are allies of Marcos.

As candidate for president in 2016, and as president until 2022, Duterte had been known to issue profanity-laden threats directed at public officials, including elected politicians, judges as well as police officers, while waging his deadly war on drugs.

Under his watch, an estimated 25 mayors and vice mayors were killed, either by police or unknown gunmen and snipers. Some of those killed were reportedly included in Duterte?s drug list.

According to the Philippine police, Duterte?s drug war killed at least 7,000 people but human rights advocates say the deaths number up to 30,000. The killings are now subject to an investigation by the International Criminal Court.

At the campaign rally on Thursday, Duterte also renewed his accusations that President Marcos has been using illegal drugs, adding that he may be ?a constant user of heroin?.

Marcos Jr and Duterte?s daughter, Sara, ran as political allies in 2022, paving the way for a historic landslide victory.

But just over a year after taking office, their alliance collapsed over allegations of misuse of public funds.

In November, Sara Duterte delivered an expletive-laden speech saying she had ordered someone to kill Marcos if she herself was assassinated.

She also accused Marcos of being a weak and incompetent leader, adding that she once imagined beheading the president.

On Wednesday, the Philippines? National Bureau of Investigation recommended that criminal charges be filed against the vice president over her alleged threats to have Marcos Jr assassinated. (Al Jazeera)

?Former Philippines president Rodrigo Duterte, centre, addresses a proclamation rally for his senatorial candidates ahead of midterm elections in May [Ted Aljibe/AFP]

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