New details on planning behind Paris attacks

Phone records obtained by a French newspaper back up claims made by the three Islamic extremists behind the Paris terror attacks that they coordinated their assault, speaking up to hours before the massacre at satirical newspaper Charlie Hebdo's office.

According to the leaked documents, which haven't been made public as they are evidence in the police investigation, Cherif Kouachi met Ahmedy Coulibaly just 10 hours before the bloodshed began, and sent him a text only an hour before Kouachi and his brother attacked Charlie Hebdo.

Coulibaly, who killed four hostages inside a Jewish grocery store before being killed in a police raid, was known to be friends with Cheirf Kouachi.

He claimed in a video made before the attacks that he coordinated with the Kouachi brothers, without giving details.

While the phone records do support the claims of coordination between the men inside France, they do not appear to suggest any close links between Coulibaly and the Islamic State of Iraq and Syria (ISIS), of which he claimed to be a member.

The Kouachis are believed to have received some training and funding from a rival militant group, the al Qaeda franchise based in Yemen known as AQAP.

There has been nothing to suggest that Coulibaly was anything more than a French-born and raised criminal who became radicalized -- likely inside a French prison, as CBS News' Clarissa Ward reports for "60 Minutes" -- where he was serving time for non-terrorism related crimes.