Venezuelan lawmaker Robert Serra killed in Caracas

Robert Serra was one of the youngest members of Venezuela's National Assembly

A lawmaker from Venezuela's governing party has been killed in the capital, Caracas.

Robert Serra, 27, and his partner Maria Herrera were found dead at their home on Wednesday night.

Mr Serra was a member of the National Assembly for the Socialist Party (PSUV) and well known for delivering passionate speeches.

According to UN figures, Venezuela has the second highest peacetime murder rate in the world after Honduras.

'Immense pain'

Interior Minister Miguel Rodriguez Torres said the two were "vilely killed here in their house, a two-storied house, on the ground floor lay the woman and on the upper floor lay Robert Serra".

He said the motive behind the killing was not clear.

"I call on members of the PSUV, on youth in political parties... on all citizens, to remain calm as we'll investigate this fully," he said.

President Nicolas Maduro wrote on Twitter that an "immense pain hits us with the killing of Robert Serra", who was considered one of the party's most promising young leaders.

"Robert, we'll follow your example, always true and firm on the path of the revolution, which you defended with such passion," Mr Maduro wrote.

His killing comes 10 days after President Maduro announced he would expand a plan to disarm civilians.

Most of the murders in Venezuela are committed using firearms.

Last year, the president introduced tough penalties for illegal weapons possession, with sentences of up to 20 years in jail.

But despite these new laws, the perception of insecurity among Venezuelan citizens remains high, correspondents say.

Earlier this year, many took part in a series of mass anti-government protests demanding increased security as well as measures to improve the economy.

Correction, 3 October 2014: Earlier versions of this story incorrectly stated Robert Serra had been shot dead.