The brothers involved in the Paris attacks had a heated argument the night before the massacres, their friends have told French media.
Brahim Abdeslam, 31, blew himself up outside a cafe, injuring 15 people, during last Friday's co-ordinated attacks.
His younger brother, Salah, is on the run after escaping across the Belgian border hours after the shootings and bombings that killed 130 people.
One of their friends told a special documentary for France 2 he heard the two brothers fighting outside his house last Thursday.
"I heard an argument. A massive argument. I leaned against the window and I saw the two brothers. They were there. They were fighting each other," he said.