A Chechen exile shot dead in a Berlin park may have been assassinated by a Russian agent, according to German media.

Key points: Prosecutors are considering the possibility of a political motive behind the killing

Prosecutors are considering the possibility of a political motive behind the killing The victim was identified by a Georgian human rights organisation as Zelimkhan Khangoshvili

The victim was identified by a Georgian human rights organisation as Zelimkhan Khangoshvili Mr Khangoshvili fought on the side of rebels, who in the 1990s sought to free Chechnya from Moscow's control

Police arrested a 49-year-old Russian man soon after last week's shooting.

Witnesses say the killer approached his victim from behind on a bicycle and shot him twice in the head, then sped off.

The suspect reportedly travelled to Berlin from Moscow via Paris a few days before the attack, and had a return ticket to Moscow.

Prosecutors are considering the possibility of a political motive behind the killing.

The 40-year-old victim was identified as Zelimkhan Khangoshvili by Georgian human rights organisation EMC, which described him as an ethnic Chechen citizen of Georgia.

It said Mr Khangoshvili had fought alongside rebels — led by Aslan Maskhadov, who was killed in 2005 — which in the 1990s sought to free Chechnya from Moscow's control.

"We have no evidence pointing towards a classic criminal motive," said Martin Steltner, spokesman for Berlin prosecutors, adding that they were considering the possibility of a political motive for the killing.

Mr Steltner said the suspect had been caught as he sought to dispose of a weapon in the nearby Spree River, along with the bicycle he had been riding.

The Russian citizen had so far exercised his right to remain silent.

Mr Khangoshvili (right) was a close associate of Aslan Maskhadov (left), the Chechen rebel leader killed in 2005. ( Facebook: Zelim Khan )

In its statement, EMC said Mr Khangoshvili had left Georgia and sought asylum in Germany after surviving an assassination attempt in Tbilisi in 2015.

Russia fought major campaigns against separatists in 1994-96 and 1999-2000 in Chechnya, a province located in the Caucasus Mountains on Russia's border with Georgia.

Many anti-Moscow fighters from those wars now live in exile and are at odds with the pro-Russian authorities in Chechnya.

Germany's capital has increasingly become home to dissidents and opposition figures who fear for their safety in their home countries.

In 2017, an exiled Vietnamese former government official was kidnapped in a Berlin park and smuggled back to Vietnam in a case that strained ties between the two countries.

ABC/wires