Three men have been arrested on suspicion of spying for China.

The Metropolitan Police said the suspects – aged 39, 43 and 68 – were arrested by counter-terrorism officers in London and Wales after being accused of assisting a foreign intelligence service.

All three men remain in custody and searches have been carried out at the addresses where they were arrested, the force added.

After the arrests, Commander Helen Flanagan, head of Counter Terrorism Policing London, said: “We have seen a significant increase in our casework relating to national security in recent years, and we continue to work extremely closely with our partners to help keep the country safe and take action to disrupt malign activity where we suspect it.”