Berlin police have launched an investigation after the unmarked grave of Reinhard Heydrich, one of Hitler’s most notorious lieutenants, was dug up last week.

The grave was discovered by a worker at the Invalidenfriedhof cemetery in the city’s northwest last Thursday morning.

Heydrich’s remains appear to have been left undisturbed.

A police spokeswoman told the newspaper BZ that there were no immediate suspects.

The grave was left unmarked to avoid it becoming a neo-Nazi shrine, but tampering with a grave can be prosecuted under German law.

There was speculation that the violators of the grave could have had inside knowledge of its occupant.

Heydrich was in charge of the Gestapo before the Second World War and was later one of the architects of the Final Solution, directing the transportation of tens of thousands of Jews from Czechoslovakia to ghettos in Minsk and Riga.

He led discussions at the Wannsee Conference of January 1942, where Nazi officials discussed how the 11 million Jews of Europe would be rounded up, even from countries like Britain and Portugal that had not yet been invaded.

Heydrich remarked during the meeting: “Any final remnant that survives will consist of the most resistant elements. These will have to be dealt with appropriately, because otherwise, by natural selection, they would form the germ cell of a new Jewish revival.”

But five months later he died of injuries following a bomb attack arranged by Czechoslovak agents. He was buried in Berlin following an earlier elaborate funeral in Prague.