Polish former Interior Minister Mariusz Kaminski said on Wednesday that he would be starting a hunger strike in prison, a day after he was arrested despite having taken refuge with political ally and President Andrzej Duda in the presidential palace in Warsaw. 

Kaminski is a senior politician with Poland's largest political party, PiS, which lost control of government in recent elections but still holds the presidency. 

"I declare that I treat my conviction... as an act of political revenge," Kaminski said in the statement, read by his former deputy, Blazej Pobozy, at a press conference.

"As a political prisoner, I started a hunger strike from the first day of my imprisonment."

President Duda, meanwhile, pledged to support Kaminski and his allies and urged people to protest peacefully should they wish to protest, as PiS supporters were expected to hold demonstrations. 

"I will not rest in the fight for a fair and just Polish state," Duda was quoted as saying in a post on his social media feed.

"I will not rest until Mariusz Kaminski and his collaborators are free. I won't be scared. I will act legally, in accordance with the Constitution and the law — as before." 

"As the one who was elected by 10.5 million Poles, I appeal for calm," Duda said. "It is allowed to gather and participate in demonstrations in Poland, but I ask that they be dignified and peaceful." 

Power struggle between old government and new, spanning decades

The charges against Kaminski and his former state secretary, Maceij Wasik, who was also arrested on Tuesday, date back to 2007. They also reflect the highly antagonistic relationship, even by the standards of robust democratic opposition, between the two largest political factions in Poland for many years.

The last time his PiS party lost power, Kaminski was accused and convicted of abuse of power while in office by the next government. 

But in 2015, as the scales swung back in PiS's favor at the polls, President Andrzej Duda pardoned them. Kaminski returned as a member of the Sejm parliament and as a minister without portfolio with PiS.

Critics argued this pardon was invalid, as it came before the politicians had exhausted their normal avenues for appeal.

Last June, Poland's Supreme Court declared that their pardons had been invalid. 

Since narrowly winning October's parliamentary elections and regaining control of parliament — but not the president's office — the coalition around Prime Minister Donald Tusk had sought to reinstigate their prosecution and detention. 

Duda, who argues his pardon for them remains valid, invited them into the presidential palace in an apparent bid to shield them from police planning to act on an arrest warrant.

Ultimately this did not work and the men were cuffed inside the building, amplifying the existing tensions between the old and new governments. Tusk accused Duda of obstructing justice by harboring fugitives.

The arrest led to protests in Warsaw, including outside the presidential palace and the police precinct that was holding the politicians. 

January 10 already a noteworthy day for PiS leaders, supporters

Supporters of PiS were set to be on the streets on Wednesday anyway by coincidence.

January 10 is the anniversary of the 2010 Smolensk air disaster in which Poland's then-President Lech Kaczynski was killed.

Kaczynski's twin brother, Jaroslaw, no longer holds senior public office but still heads the PiS party and is still seen as its driving force. He laid a wreath at a Warsaw memorial service on Wednesday.

Kaczynski and PiS are among those promoting the notion that the crash was no simple accident caused by unsafe flying, as both Russian and Polish investigators formally concluded at the time. He has also accused the Polish government of the time, which was led by Tusk's Civic Coalition, of helping cover up any potential Russian complicity.

msh/wmr (dpa, Reuters)