BRATISLAVA (Reuters) - The leader of Slovakia’s far-right People’s Party-Our Slovakia has been charged with extremism for “sympathizing with a movement aiming to suppress basic rights and freedoms”, police said on Friday.

Authorities announced the charges against Marian Kotleba - originally brought last week - in a one-sentence statement that provided no further details. He faces up to three years in jail if convicted.

Local media reported that the charges are related to pictures the People’s Party posted online in March. Those pictures showed an enlarged copy of a check donated to a charity for disabled children -- for 1,488 euros.

The numbers supposedly carry a white-supremacist and pro-Nazi message. The 14 refers to the 14 words in a slogan used by white supremacists: “We must secure the existence of our people and a future for white children.” The 88 is short for “Heil Hitler” -- “H” is the eighth letter of the alphabet.

Right-wing and anti-immigrant parties have been on the rise across Europe after years of slow economic growth and the arrival of more than a million migrants and refugees from the Middle East and Africa.

Slovakia has seen little immigration, but rising public anger over graft scandals linked to conventional parties has generated support for far-right parties.

In an electoral shock, 14 lawmakers from the People’s Party-Our Slovakia, including Kotleba, won seats in the Slovak parliament last year after winning 8 percent of the vote. Support has since risen to about 10 percent, according to opinion polls.

Two of the party’s lawmakers are already facing charges for hate speech against Roma, Jews and Muslims. Prosecutors took steps in May to ban the entire party, saying it posed a threat to Slovakia’s democratic system.

The party denies any links to fascism. But it openly admires Jozef Tiso, the leader of the 1939-1945 Nazi puppet state, who allowed tens of thousands of Slovak Jews to be deported to Nazi death camps and who was tried for treason after the war.

“The police have adopted double standards in treating the Prime Minister and the opposition,” Kotleba told journalists on Friday, pointing to an earlier statement by Fico that “Hitler had a good economic program”.

Leftist Prime Minister Robert Fico has been also criticized by human rights groups and socialist colleagues in the European Parliament for stirring anti-Roma sentiment and for refusing to accept the EU quotas on accepting refugees, saying in a May 2016 interview “there is no space for Islam in Slovakia”.