Police arrested a man in Northern Ireland on Wednesday in connection with the 1974 bombings of two pubs that killed 21 people and injured more than 200 in Birmingham, England.

Officers from the West Midlands counterterrorism unit, working with colleagues from the Police Service of Northern Ireland, arrested a 65-year-old man at his home in Belfast, West Midlands Police said. The man was arrested under Britain’s Terrorism Act, and his home was being searched, authorities said.

The arrest came days before the 46th anniversary of the two November 21, 1974 blasts that ripped apart the Mulberry Bush and Tavern in the Town pubs in the city of Birmingham. The blasts were one of the worst attacks committed by the Irish Republican Army during its armed campaign to get Britain out of Northern Ireland.

British Home Secretary Priti Patel said a month ago that she would consider holding a public inquiry into the bombings.

Julie Hambleton, whose 18-year-old sister Maxine died in the bombings, said the arrest was “the most monumental event” in the criminal investigation into the bombings since the 1975 murder convictions of six Irishmen, widely referred to as the Birmingham Six, were thrown out in 1991.

Hambleton said she broke down in tears when a senior West Midlands Police officer telephoned her with news of the arrest.

“I couldn’t speak. I was just inconsolable and was just looking at the picture of Maxine,” she said. “It’s welcome news. It’s overwhelming news.”

Hambleton, who is part of an advocacy group called Justice for the 21, said that whatever happens with regard to the arrest “does not in any way lessen our desire for a full public inquiry to be held”.

She said there are “wider issues” that need to be examined, including “why six men were arrested for a crime they didn’t commit”.

“How was it that for so long, after 21 people were blown up and more than 200 other innocent souls were injured, nobody was looking for the perpetrators?”