British police have opened an investigation into explicit messages sent to a lawmaker as part of an alleged sexting scam targeting MPs, in the latest cybersecurity scare to hit parliament.

Conservative MP William Wragg acknowledged late Thursday that he had sent personal phone numbers of several colleagues to a man that he met on a gay dating app.

Wragg, 36, told The Times newspaper he did so under pressure, as the recipient claimed to have compromising material on him.

"I was worried because he had stuff on me. He gave me a WhatsApp number, which doesn't work now," said the MP, who is standing down at the next election.

"I've hurt people by being weak. I was scared. I'm mortified," he was quoted as saying.

The scam has been described as a "spear phishing" attack, which sees supposedly trusted senders steal personal or sensitive information.

Last month, the UK government summoned China's top envoy in London to complain about a series of cyberattacks, including against MPs, and previous claims of espionage against lawmakers by Beijing.

There was no explicit evidence of Chinese involvement in the targeting of Wragg and his colleagues, which was first reported by Politico this week.

But it will again raise questions about cybersecurity for MPs and in the UK parliament as a whole.

According to The Times, two MPs also responded to the initial message to them with explicit personal photos. 

And Leicestershire Police in central England said officers were "investigating a report of malicious communication" sent to a local MP last month.

"They were reported to police on Tuesday March 19. Inquiries are currently ongoing," a statement read.