MANILA--Human rights groups asked the Philippine Commission on Elections to disqualify the son and namesake of late dictator Ferdinand Marcos from running for president in next year’s elections, saying he was convicted of tax evasion, could no longer hold public office and kept the damaging details from the public.

Ferdinand “Bongbong” Marcos Jr.’s spokesman, Victor Rodriguez, on Wednesday called the petition “propaganda” and said they would address “this predictable nuisance” when they receive a formal copy of it. The issue, which should be resolved by elections commissioners before the May 9 vote, could spark a legal battle that could go all the way to the Supreme Court.

Marcos Jr. registered his candidacy early last month, angering activists who recalled the widespread human rights atrocities and plunder that marked the martial law era under his father, who was toppled in an army-backed “people power” revolt in 1986. The ousted president died in exile in Hawaii three years later without admitting any wrongdoing, including accusations that he and his family amassed an estimated $5 billion to $10 billion while he was in power.

Marcos Jr. has called the allegations against his father “lies.”

At least six groups of petitioners asked the elections commission Tuesday to either cancel or reject Marcos' candidacy because of “false material representation” for declaring his eligibility to run despite his 1995 tax evasion conviction.

“Petitioners claim that Marcos is not eligible to run for any public office as he is, plainly, a convicted criminal,” the groups said in their joint petition. His declaration of eligibility to seek public office “was made with the deliberate intent to mislead, misinform and deceive the electorate.”

Marcos Jr. was convicted in July 1995 of failing to file mandatory income tax returns from 1982 to 1985, a decision which was upheld by Manila’s Court of Appeals. The conviction became final in 2001, when he withdrew his appeal before the Supreme Court, making him ineligible to hold any public office under the law, according to the petitioners and their lawyer, Theodore Te.

It’s unclear how Marcos Jr. managed to stay as governor of northern Ilocos Norte province until 2007, unless his conviction was overlooked by the government or nobody challenged it. In 2010, he successfully ran for a Senate seat, and in 2016, he sought the vice presidency but was narrowly defeated and then unsuccessfully challenged the results.

The petitioners also accused Marcos Jr. and his family of failing to pay estate taxes with penalties and interests of more than 203 billion pesos ($4 billion) following his father’s death in 1989 in Hawaii despite repeated government demands. The crime involved “moral turpitude,” which should be another reason for him to be barred from any government post, the petitioners said.

Ferdinard Marcos placed the Philippines under martial rule in 1972, a year before his term was to expire. He padlocked Congress and newspaper offices, ordered the arrest of political opponents and ruled by decree.

A Hawaii court found him liable for human rights violations and awarded $2 billion from his estate to compensate more than 9,000 Filipinos who filed a lawsuit against him for torture, incarceration, extrajudicial killings and disappearances.

His widow, Imelda Marcos, and her children were allowed to return to the Philippines in 1991, and have since made a political comeback, winning seats in Congress and powerful provincial posts and laying the ground for a return to the presidential palace and the top job they felt was stolen from them.

Marcos Jr., 64, is one of at least five key candidates who have declared their intention to succeed President Rodrigo Duterte, who has been in the crosshairs of human rights groups himself for a brutal crackdown on illegal drugs that has left thousands of suspects dead.

The aspirants include Vice President Leni Robredo, the opposition leader who narrowly defeated Marcos Jr. in the 2016 vice presidential race. She has criticized him for his refusal to apologize and express remorse for the massive abuses under his father’s brutal dictatorship.