Harlow (United Kingdom) (AFP) - Poland's ambassador to Britain on Wednesday condemned a rise in xenophobic attacks after the Brexit referendum, speaking where a Polish man was murdered in what police believe could be a hate crime.

"This situation is much worse after the Brexit referendum," Arkady Rzegocki said in Harlow, a working-class town northeast of London, after laying a bunch of flowers where Arek Jozwik was killed.

"It could be a hate crime but we're not sure," Rzegocki told AFP after meeting the family of the murdered man, who was attacked on Saturday.

Six local teenagers have been arrested and released on bail pending further investigation following the attack on the 40-year-old factory worker, in a run-down open air shopping centre in the town.

The man's brother Radek Jozwik, 36, was quoted as saying in The Sun daily: "The police have told us he was attacked because they heard him and his friends speaking the Polish language".

Jowzik died of head injuries on Monday.

The Polish foreign ministry said it would raise the issue of attacks on Polish citizens living in Britain when Foreign Secretary Boris Johnson visits Warsaw on Saturday.

A 43-year-old man was also injured in the attack and discharged from hospital after being treated for suspected hand fractures and bruises to the stomach.

- 'Everywhere is dangerous' -

Harlow MP Robert Halfon, who visited the area with the ambassador, said the referendum was "being used by people who come from the sewers who want to exploit division and have their own racist agenda".

Police have said one line of investigation is that it was a hate crime and have appealed for witnesses.

Harlow has one of the highest concentrations of Eastern European immigrants in Britain.

But local residents in the part of town where the murder happened, known as The Stow, blamed high crime levels in the area more than racism.

"People don't really come into The Stow no more because of the youngsters," said Tom Sladden, a 24-year-old warehouse worker.

Story continues

Emily Shakeshaft, 22, a cleaner, said: "You might look at someone funny and you might get whacked in the face".

Jecek Gora, who owns a Polish shop in the area, said he did not believe Jozwik was singled out for being Polish.

"Everyone knows about the teenagers. That's the problem... Everywhere is dangerous," Gora said.

There were several xenophobic attacks in Britain before and after the June 23 referendum including graffiti daubed on a Polish cultural centre in London, which was condemned by the government.

The National Police Chiefs' Council said more than than 3,000 incidents were reported to police across the country between June 16 and 30 -- an increase of 42 percent from the same period last year.