BEIJING - The killing of an anti-Brexit lawmaker has aroused global reaction as a June 23 referendum on whether Britain will remain in the European Union (EU) is drawing near.

Jo Cox, 41, a lawmaker from the opposition Labour Party and a vocal advocate for Britain staying in the EU, was attacked while preparing to meet constituents in Birstall near Leeds in northern England.

The Yorkshire Post newspaper reported the 41-year-old mother of two was shot and stabbed by a man reportedly shouting "Britain first."

The police said a 52-year-old man has been arrested in connection with the murder but his motive remains under investigation.

"Britain First" is the name of a far-right anti-immigration group. The group released a statement saying it was "obviously not involved" and "would never encourage behavior of this sort."

After the attack, pro- and anti-Brexit groups said they were suspending all campaigning for Thursday and Friday ahead of the EU membership referendum.