Spain’s far-right Vox party has suspended one of its senior regional members and apparently set about deleting references to him on social media after he was arrested on suspicion of sexual offences.

Officers from the Catalan police force, the Mossos d’Esquadra, arrested José Antonio Ortiz Cambray, 53, on Tuesday afternoon in the city of Lleida after receiving information that prompted them to open an investigation.

“A man of Spanish nationality was arrested yesterday afternoon in Lleida in connection with that investigation,” a Mossos spokesman said.

“The allegations are of crimes against sexual freedom. We cannot go into more details or say whether the victims were adults or minors.” Vox confirmed that Ortiz had been arrested, but disputed reports that he was its local leader.

The party was accused of trying to purge references to Ortiz after social media users turned up official Vox photos describing him as the party’s president in the city. The page that had housed the names of Vox’s Lleida team was also blank on Wednesday morning.

In a statement on Twitter, the party said Ortiz was “a Vox member in Lleida” and “holds no position of responsibility within the party and is only a local activist. Vox has decided to suspend his membership until the facts become clear, allowing an informed decision to be taken.”

The party also said it was in favour of “toughening of penalties for certain crimes, including those which been mentioned in the press reports published”.

Ortiz ran as a senate candidate in the 2015 general election, winning 0.08%, and again the following year, when he took 0.21%.

“Mr Ortiz has never been president of Vox in Lleida, although he has presented himself as such,” a Vox spokesman told the Guardian.

“It’s true that he did put himself forward as a candidate to lead the regional branch, but he was rejected by the national executive committee, which is the party’s most senior decision-making body.”

The spokesman did not comment on the deletion of social media messages that referred to Ortiz as the party’s leader in Lleida.

In December last year, Vox became the first far-right group to triumph at the ballot box since Spain’s return to democracy after the death of Francisco Franco in 1975.

The small but increasingly vocal party, which opposes Catalan independence and has vowed to take a tough line on immigration, abortion and domestic violence legislation, exceeded all predictions to take 12 seats in the Andalucían regional election.

It subsequently opted to support a government led by the rightwing People’s party and the centre-right Citizens party.