Police in the western German city of Oberhausen on Tuesday scoured the scene of an explosion at the local offices of the socialist Left Party.

The party says it believes there was a far-right political motive behind the explosion, with police saying they are examining all possible leads.

What do we know about the explosion?

The blast at about 3:20 a.m. local time (01:20 UTC/GMT) blew out windows at the party offices and damaged the interiors of other nearby businesses, including a hairdressing salon and a travel agent. The explosion was reportedly so strong that panes of glass were even damaged on the opposite side of the road.

"According to our current knowledge, fortunately, no one was injured by the explosion," police for the state of North-Rhine Westphalia, where Oberhausen is located, tweeted.

In a statement, police said forensic investigations were underway at the scene with assistance from state explosives experts. 

Police added that the State Security division of the Federal Criminal Police Office (BKA) was involved in the investigation because of a possible political motive. 

"The evaluation of the traces and the investigations are ongoing," the statement said.

The German press agency DPA cited sources close to the investigation as saying evidence of an explosive device had been found.

It said an "unconventional explosive and incendiary device" could be responsible,  built with, among other things "flash explosives" like those contained in fireworks.

Why might the party have been targeted?

In a written statement on Facebook, Yusuf Karacelik, party chair in Oberhausen, said he assumed it was a "targeted attack from the right."

"In the past, there were repeated stickers from the neo-Nazi spectrum on our premises, as well as isolated threatening letters," he said.

Karacelik also confirmed to DPA that police had asked about any possible connection to local party's participation in a demonstration in Berlin against the rearmament of Germany after Russia's invasion of Ukraine.

The Left Party's national leader Janine Wissler also said she believed there was likely a right-wing political motive.

Party supporters took to Twitter to complain that the police had not instantly deemed the explosion to be politically motivated. 

Police acknowledged that they were aware of the discussion, and said investigations were ongoing.

"We are also observing the discussions on social media and would like to point out once again that we cannot rule out a political motivation, but we cannot confirm it either."

The party is the most left-wing force in the German parliament but has only 39 seats in the 736-seat assembly after garnering 4.9% of votes in national elections last year.

The Left Party (Die Linke in German) was formed in 2007 when disenchanted members of the Social Democratic Party (SPD) and trade unions forged a pact with the eastern German post-communists.

The fact that some of the Left's members were once part of the Socialist Unity Party (SED), which ran the East German dictatorship, still puts many German voters off — especially older ones.

While the Left Party has condemned the invasion of Ukraine, a vocal minority within the party has blamed NATO's expansion in eastern Europe. Ahead of the 2021 national election, the party said it wanted to replace NATO with a collective security system involving Russia.

It also called for an end to all Bundeswehr missions abroad, and for Germany to stop all weapons exports.

rc/rt (AFP, dpa)