The Spanish separatist group ETA has handed over weapons to French police as part of its decision to disarm.
The militant group surrendered the locations of eight stores of weapons hidden in the Pyrenees-Atlantiques and Hautes-Pyrenees in southwestern France.
France has called the move - which has been verified by an international group overseeing the process - a "major step" and "an undeniably important day".
Eight caches of weapons containing 120 firearms, three tonnes of explosives and several thousand rounds of ammunition are understood to be stored on the sites.
Security forces are now searching the sites to neutralise the explosives and secure the weapons.
This surrender follows more than 40 years of violence aimed at Basque independence.
Founded in 1959, the group has been blamed for the deaths of more than 850 people in a string of bombings and shootings.
Earlier in the week ETA said it would give up all of its remaining weapons by Saturday, dubbed "Disarmament Day".
At the peak of the ETA's violence, a 1987 car bomb at a Barcelona supermarket drew international outrage after it killed 21 including a pregnant woman and two children.
The last victim was a French policemen shot in 2010.
Last year an ETA member was sentenced to 92 years in prison over a plot to kill the former Spanish king after being arrested in the UK.
If the disarmament is successful, it will mark the end of one of western Europe's longest-running recent armed political struggles.
ETA called a permanent ceasefire in March 2006, but the promise was broken later that same year after a bomb in Madrid killed two people.
In 2011 - amid pressure from police and decreasing public support - ETA said that it had abandoned its armed campaign, announcing a formal, definitive and permanent truce. However it did not give up its arms.
More recently it has attempted to negotiate its dissolution in exchange for amnesties for roughly 350 ETA prisoners held in Spain and France; however, both countries refused any concessions.
The Spanish government has downplayed the disarmament as a unilateral affair and said the group could expect "nothing" in return.
Spain's culture minister said: "It will not reap any political advantage or profit. May it disarm, may it dissolve, may it ask forgiveness and help to clear up the crimes which have not been resolved."
There are more than 300 unresolved murders from ETA's five-decade terror campaign, and it is not clear if potentially incriminating weapons involved will be handed over or destroyed.
It is unknown if dissolution of the group will follow the handover.