A second suspect was arrested Saturday on arson charges in connection with a series of fires targeting property linked to U.K. Prime Minister Keir Starmer, police said.

A 26-year-old man was arrested at Luton Airport on suspicion of conspiracy to commit arson with intent to endanger life, police said.

The arrest came the day after a Ukrainian man appeared in court on charges of setting fire to Starmer's personal home, along with a property where he once lived and a car he had sold. Police didn't provide the nationality of the second suspect.

No injuries were reported from the fires, which occurred on three nights in north London between May 8 and May 12.

Roman Lavrynovych, 21, didn't enter a plea Friday in Westminster Magistrates’ Court to three counts of arson with intent to endanger life.

Lavrynovych denied setting the fires and, at this point, there is no explanation for the crimes, a prosecutor said.

Starmer and his family had moved out of his home after he was elected in July, and they live at the prime minister’s official Downing Street residence.

A Toyota RAV4 that Starmer once owned was set ablaze on May 8 — just down the street from his house. On Sunday, an apartment building where the politician once lived was set on fire. On Monday, the doorway of Starmer’s home was charred after being set ablaze.

Counterterrorism detectives led the investigation because it involves the prime minister. The charges were authorized by the Crown Prosecution Service’s Counter Terrorism Division, which is responsible for prosecuting offenses relating to state threats, among other crimes.

Starmer and leaders across the House of Commons condemned the fires earlier this week. Starmer called them “an attack on all of us, on democracy and the values that we stand for.”