Merera Gudina was arrested after he appeared at the EU parliament to testify on current political crisis in Ethiopia.

A prominent Ethiopian opposition leader from the country’s restive Oromo region has been arrested after he came back from a meeting with members of the European Parliament in Brussels.

Merera Gudina, who is the chairman of the opposition Oromo Federalist Congress, was arrested in his house in the capital Addis Ababa, according to media reports.

“Merera arrived in Addis Ababa on Wednesday morning from a trip to Brussels, where he met members of the European Parliament,” Gebru Gebremariam, deputy chairman of the Oromo Federalist Congress, told the Reuters news agency.

READ MORE: Ethiopia – Oromo protests continue amid harsh crackdown

“Police arrested him in his house the same day in the evening. We haven’t been given reasons behind his arrest,” Gebru added.

Ethiopia’s state-aligned FBC radio said the Oromo leader was arrested for “trespassing the state of emergency rulings of the country”.

A six-month state of emergency was declared in October after almost a year of violent protests, giving the authorities the power to restrict opposition activities and impose curfews. Last month, the government said more than 11,000 people had been arrested since the decree was passed.

Merera was arrested for violating the directive stated under article 2, which prohibits any communication with “banned terrorist organisations and anti-peace groups,” FBC said.

Before his arrest, Merera had appeared at the EU parliament to testify on the political crisis and human rights violations in Ethiopia.

He was joined by two other prominent opposition figures: Berhanu Nega, leader of the banned Patriotic Ginbot 7 group and athlete Feyisa Lilesa, an Olympic silver medalist who carried the Oromo protests that gripped Ethiopia in to international headlines when he crossed his arms in an X sign at the finishing line in Rio.

Merera is being held at the Ma’ekelawi prison, according to the Addis Standard.

READ MORE: Ethiopia – Dozens killed in Oromia festival stampede

Sporadic protests have erupted in Ethiopia’s Oromia region over the past two years, initially sparked by a land row and increasingly turning more broadly against the government.

Merera Gurdina had been vocal about alleged human rights abuses against Oromo people committed by the government

According to New York-based Human Rights Watch, at least 500 people have been killed by security forces since the demonstrations began in November 2015.

Though protests started among the Oromo, Ethiopia’s biggest ethnic group, they later spread to the Amhara, the country’s second largest ethnic group.

Both groups say the ruling coalition is dominated by the Tigray ethnic group, which makes up only about six percent of the population.

The government has blamed rebel groups and dissidents abroad for stirring up the protests and provoking violence.

Authorities have denied that violence from the security forces is systemic, though a spokesman previously told Al Jazeera that police officers “sometimes take the law into their own hands”, pledging an independent investigation.

The Ethiopian People’s Revolutionary Democratic Front, the ruling party, in October rejected a United Nation request to send in observers, saying it alone was responsible for the security of its citizens.