"It had a big effect on me," Francis Collomp said in one of the first interviews he has given since his escape from the Nigerian rebel group Ansaru. "But it also meant this: Ansaru is linked to Aqim [Al-Qaeda in the Islamic Maghreb] and they have never left a hostage alive. After the emotion, it gave me the energy to think about my escape again, and to study all the details that could make it happen."
He said his kidnappers made various political demands, including the withdrawal of French troops from Muslim countries and the release of Ansaru prisoners.
Collomp also thanked RFI, saying that he listened to its broadcasts constantly while in captivity.
The French engineer, who was taken hostage 11 months ago in northern Nigeria, had kept himself fit in the small room in which he was held captive so as to be ready to escape.
He managed to run away thanks to a mistake by one of his captors.
"He had to come into my cell to get to another sort of bathroom where water was stored in a large bin," Collomp explans. "Instead of locking the door and keeping the keys with him to wash himself before prayer, he left the keys outside the door. I let him start his ritual and I opened the door very softly. I had prepared a small piece of metal to push the keys out and I put it back into the lock so that the keys would not go back in. I had it all worked out."
He then ran the 300-400 metres to a road, slowing down once he encountered people and vehicles so as not to attract attention.
He then hailed a motorbile-taxi and asked to be taken to the nearest police station.
Collomp only found out where he was being held - in small town called Zaria - once he was free.
He had been moved there from the major town of Kano because he had realised he was there thanks to RFI, he says.
At 6.30am he had heard two explosions and later that day RFI reported that two bombs had gone off in the town.
Ansaru is a split-off from Nigeria's hard-line Islamist Boko Haram group.
The two groups reportedly collaborated in the recent kidnap of French priest Georges Vandenbeusch in northern Cameroon, taking him over the border to Nigeria.