MANILA: Security forces fanned out across the Philippines on Sunday on the eve of national polls, following a vicious and deadly election campaign dominated by presidential favorite Rodrigo Duterte’s threats to kill thousands of criminals.

Surveys show Duterte, mayor of the southern city of Davao, has a clear lead in Monday’s presidential elections as millions of voters embrace his threats to unleash security forces in an unprecedented crime spree, and shut down Congress if lawmakers oppose him.

President Benigno Aquino, who is limited to a single six-year term, has likened Duterte to Nazi leader Adolf Hitler and warned of a looming dictatorship, with the presidential tensions fueling an already volatile and violent political culture.

“Their rhetoric is quite vicious, their exchanges are quite vicious and this is a signal to a lot of supporters to up the ante and be more aggressive,” Eric Alvia, head of the watchdog group, National Citizens Movement for Free Elections, told AFP.

“This campaign has been divisive and its polarizing a lot of people. They (feel they) can do whatever they want.”

Duterte has accused Aquino’s administration of planning “massive cheating” to ensure that his preferred successor, former interior secretary Mar Roxas who surveys show is trailing in second place, wins.

His followers have warned of a “revolution” if Duterte loses, while military-linked figures have threatened a possible coup attempt if he wins.

Alvia said that the violence was largely taking place on the local levels, but with the leaders’ angry rhetoric fueling matters.

At least 15 people have died in election-related violence this year, according to national police statistics.

In the latest suspected case, a grenade blast killed a nine-year-old girl behind the house of a powerful political warlord in the strife-torn province of Maguindanao late on Saturday, said Chief Inspector Jonathan del Rosario.

Her death has not yet been included in the tally although it likely will be, according to del Rosario, spokesman for a police election-monitoring taskforce in Manila.

“This looks like it is election-related but we have a process we have to follow,” del Rosario told AFP.

In the wake of the blast, armored vehicles could be seen patrolling the streets of the town while soldiers in camouflage stood guard on vital chokepoints.

Del Rosario said 90 percent of the nation’s police force, or about 135,000 officers, were already on election-related duty and had been authorized to carry their assault rifles.

The military has said their forces are also on election duty.

Del Rosario said policemen were guarding polling and canvassing places and manning road checkpoints and were even acting as election officials in a few towns that have been identified as “election hotspots,” due to the heated rivalry between politicians.

With more than 44,000 people running for 18,000 positions ranging from president to town councillor, the competition has also resulted in a surge of vote-buying.