The tomb of Karl Marx in Highgate cemetery in London has been vandalised for the second time in the space of a month.

The words “doctrine of hate” and “architect of genocide” were found daubed in red paint across the Grade I-listed monument in the north London graveyard on Saturday.

The latest attack comes less than two weeks after the marble plaque on the tomb was defaced by an apparent attempt to scrape and chip Marx’s name off the marble slab with a hammer.

At the time the group who manage the cemetery – the Friends of Highgate Cemetery Trust – said they feared the memorial would never be the same again.

Maxwell Blowfield, 31, who visited the cemetery this morning with his mother admitted he was “quite shocked” by the attack.

Blowfield, 31, who works for British Museum, said: “It’s a highlight of the cemetery. The red paint will disappear, I assume, but to see that kind of level of damage and to see it happen twice, it’s not good.

“I wouldn’t like to say who or why someone did it but it was clearly someone very critical of Marx and that part of history. I am just surprised that somebody in 2019 feels they need to and do something like that.”

After the hammer attack earlier this month, the Friends of Highgate Cemetery Trust branded it a “deliberate and sustained attack”.

Ian Dungavell, the trust’s chief executive, described the attack as “very upsetting”.

Speaking to the Guardian at the time he said: “We think it was deliberately targeted against Karl Marx. It was not random. You can see from the photograph that the person has really done their best to obliterate Karl Marx’s name.”

The plaque was first used on the grave of Marx’s wife, Jenny von Westphalen, in 1881 and was moved when the remains of Marx and his wife were exhumed and reinterred in a more prominent location in the cemetery in 1954.

The monument is owned by the Marx Grave Trust, which is represented by the Marx Memorial Library in Clerkenwell.

Highgate Cemetery tweeted that the memorial had been vandalised in a “Senseless. Stupid. Ignorant” attack.

Vandals back at Marx Memorial, Highgate Cemetery. Red paint this time, plus the marble tablet smashed up. Senseless. Stupid. Ignorant. Whatever you think about Marx's legacy, this is not the way to make the point. pic.twitter.com/hGKBMYGWNy — Highgate Cemetery (@HighgateCemeter) February 16, 2019

The Metropolitan police said they had received a report of criminal damage at around 10.50am on Saturday.

A spokesman said: “There have been no arrests. We would appeal to anyone who has any information to contact us.”

He also confirmed no arrests had been made over the 4 February attack.