Hungary's government accused the Belgian capital of trying to censor it on Thursday after a van it commisioned to drive through Brussels with a billboard linking migration to terrorist attacks was stopped by police.

Zoltan Kovacs, Hungarian secretary of state for international Communications and relations, made the accusation in a video posted on Facebook. He said the truck had been stopped by police on December 5 and that the driver had been arrested.

Kovacs said the intervention was unacceptable, arguing that nothing illegal had been done and that the Hungarian government had the right to express its opinion.

Brüsszelben be akarják tiltani a kormány kampányát Brüsszelben be akarják tiltani a kormány kampányát, amelyben a bevándorlás következményeire hívja fel a figyelmet. Tegnap megállították a plakátos autót, és arra kényszerítették a sofőrt, hogy szedje le a feliratot. Guy Verhofstadt elmondhatta a véleményét, de nekünk meg akarják ezt tiltani. A kormány azonban ragaszkodik ahhoz, hogy a magyar álláspont is megjelenjen. Publiée par Magyarország Kormánya sur Jeudi 6 décembre 2018

Police in Brussels confirmed to Euronews that they had intervened and that an official report had been drawn up against the driver but did not disclose on what grounds.

The mobile billboard featured pictures of two terror attacks on European soil, which took place in 2016 — at Brussels' Zaventem airport and in the French coastal city of Nice.

It also displayed a picture of MEP Guy Verhofstadt, leader of the liberal ALDE group in Parliament and a fervent critic of Hungarian Prime Minister Viktor Orban.

It said: "Hundreds have died in terrorist attacks since 2015 but Guy Verhfstadt says: "We don't have a migration crisis". This is insane!" suggesting there is a link between immigration and terror attacks.

The Hungarian government's stunt was inspired by Verhofstadt himself. Last month, the MEP used a billboard mounted on a truck to criticise Orban, saying: "First he took our money, now he wants to destroy Europe."

Verhofstadt also called on Orban "do better" when Hungary revealed its own truck would be deployed to Brussels.

In a post published later on Friday on the Hungarian government's Facebook page, it appeared the campaign van was back on the streets of Brussels.

A controversial figure, Orban was reelected for his third consecutive term in April. He is one of the chief opponents to proposed EU migrant resettlement quotas and has introduced a slew of anti-migrant policies.

A Hungarian government spokesperson told Euronews: "The Government recently commissioned a van displaying a billboard which warns of the consequences of pro-immigration policies. This was stopped by police in the streets of Brussels and the driver was told to remove the image of Guy Verhofstadt. The case shows that there is greater vitality in Central and Eastern European democracy than in its Western European variant."

The article was amended as an earlier version erroneously said "EU" instead of "Brussels."