The source said Wael Abbas, described by Lebanese officials as the mastermind of the kidnapping in March, appeared to have been stopped as he tried to cross from Lebanon into Syria.

The seven Estonian cyclists were abducted shortly after arriving in Lebanon from Syria. They were freed unharmed four months later but the circumstances of their kidnapping — a rarity since the end of Lebanon’s civil war in 1990 — remain unclear and officials did not say whether a ransom was paid.

A Lebanese security source familiar with the case said the Estonians were released after negotiations but gave no details. The area of the Bekaa Valley where they were captured is known for lawlessness and gangs involved in car thefts operate there.

In April, Lebanese authorities charged 11 people — four of whom they said at the time were still at large — with abducting the tourists at gunpoint and shooting at a security force patrol.

In September security forces killed two men they said had been involved in the kidnapping.