Authorities arrested a 54-year-old man Monday in connection with last year’s execution-style murders of an English family in the French Alps.

The man, who was only identified as being 54 years old, was arrested around 7:30 a.m. in Surrey, according to a statement issued Monday by the Surrey Police. He was charged with suspicion of conspiracy to commit murder.

While the statement did not give the man’s name, he was identified in The Mirror as Zaid al-Hilli, the brother of Saad al-Hilli, the 50-year-old engineer who was killed along with his wife and her mother in the French Alps town of Chevaline on September 5, 2012.

Surrey Police gave few details as to how they allegedly linked the 54-year-old to the murders of the al-Hillis and Suhaila al-Allaf, the wife’s mother. The investigation determined that the al-Hillis’ BMW was sprayed with gunfire. The barrage of bullets also killed a French cyclist, Sylvain Mollier.

The al-Hillis’ daughters survived the French Alps shooting. Zeena al-Hilli, 4, hid under her mother’s corpse until authorities arrived while Zainab, 7, was severely injured in the attack.

Surrey Police were working with French police to solve the French Alps shooting.

“As part of the Joint Investigative Team (JIT), which was established Sept. 21 last year, officers from the Surrey and Sussex Major Crime Team have been working closely with French authorities to progress a number of lines of inquiry,” the statement went on to say.

The arrest of the 54-year-old was “pre-planned,” according to the statement, and was “a result of these ongoing inquiries and any updates will be issued in due course.”

Reports surfaces that Zaid al-Hilli feuded with his brother over an inheritance, but al-Hilli denied that he fought with his younger brother over money.

The killings shocked the world at the time and remained a mystery for nearly a year until Monday’s arrest.

At the time, the chief prosecutor of Annecy, France, indicated that the investigation would be a lengthy one.

"We're investigating everything but it all takes a lot of time, trying to piece together the lives of all the people who have died, trying to perhaps understand a real motive, the real reasons for these killings,” said Eric Maillaud, according to The Mirror. “"Perhaps if we can understand why they were killed we can work out who killed them, but at the moment there are many questions. I think the investigation will take a very, very long time, unless we discover something that will suddenly enable us to understand everything."