London police arrested four men across the city Tuesday in an ongoing investigation into Islamist-related terrorism, Scotland Yard said in a statement.

Authorities said the men, who are in their early 20s, were arrested after warrants were executed at various addresses. One of the men was tasered, but did not require medical attention, a statement obtained by Fox News said.

Con Coughlin, the defense editor at The Telegraph, told Fox News that sources said there was an ISIS plot for British jihadist to behead people in the streets of London within the next few days.

The men were arrested on the charge of Preparation or Instigation of acts of Terrorism, which falls under the Terrorism Act.

No shots were fired during the arrests and the men have been taken to police stations in the central part of the city.