A huge manhunt was under way in Paris Tuesday for a lone gunman who shot and critically wounded a newspaper photographer in his office before opening fire outside a bank headquarters and hijacking a car.
Officers on foot and in squad cars fanned across the nervous city, taking up positions outside media offices, along the Champs-Elysees avenue and at entrances to underground train stations.
Investigators have so far been unable to identify the gunman, described by French Interior Minister Manuel Valls as "a real danger."
A source close to the investigation said the police had "received several hundred calls" following an appeal for information from the public.
"We have to obviously verify these, but they allow us to advance," the source said, adding that they were also studying shots of the man captured on close circuit television and other leads.
His motive remains unclear, but police believe the man was also behind an incident on Friday in which staff at a Paris television station were threatened by a gun-wielding intruder.
More from GlobalPost: Paris shootings: Police hunt gunman who fired on newspaper office, bank
The attacker, wearing a cap and wielding a 12-gauge shotgun, opened fire at the offices of left-wing newspaper Liberation at about 10:15 a.m. Monday.
A photographer arriving for his first day of freelance work at the paper suffered buckshot wounds to the chest and stomach.
Liberation said he was 23 years old and was originally from the southern city of Toulon.
He was taken to hospital in critical condition. The newspaper later said he underwent surgery and was being kept in intensive care.
Liberation executive Nicolas Demorand said on Tuesday the man was "still critical," although he was "in a slightly better state."
"He was in a hopeless state yesterday when he was hospitalised," Demorand told France Inter. "He is however in a critical state and we remain hopeful."
After fleeing the daily's offices in the east of Paris, the same man is believed to have crossed the city to the La Defense business district on its western edge, where he fired several shots outside the main office of the Societe Generale bank, hitting no one.
He then reportedly hijacked a car and forced the driver at gunpoint to drop him off close to the Champs-Elysees in the centre of the French capital, where gun crime is rare.
There were rumours that the man was armed with grenades as well as the hunting-style pump-action shotgun used in the two shootings.
'Next time I will not miss'
Police said security camera images of the shooter suggested he was the same man who last Friday stormed into the Paris headquarters of TV news channel BFMTV to threaten staff.
In that incident, the gunman pumped his shotgun to empty several cartridges on the floor, while warning a senior editor: "Next time, I will not miss you."
"Given the similarities in the four incidents, between the modus operandi, the physical appearance and attire of the perpetrator, and also in the ammunition gathered, we believe we are dealing with a single perpetrator," Paris prosecutor Francois Molins said.
Prosecutors released photographs of the man taken from surveillance camera images and described him as white, aged between 35 and 45, of average height, with salt-and-pepper hair and stubble.
Demorand said the shooting in the Liberation's entrance hall left staff traumatised but the paper vowed to carry on its work.
A commentary in Tuesday's edition of the paper signed by Demorand is headlined simply: "We will continue."
The daily devoted four pages to the unprecedented attack and an employee described the moment the gunman walked in.
"The guy pulled out a gun from his bag and fired twice at the first person he saw. It lasted no more than 10 seconds, and anyone of us could have been hit. The shooter said nothing and left immediately," the staff member was quoted as saying.
Gunman 'not panicked at all'
Philippe Antoine, the editor-in-chief of BFMTV, came face-to-face with the attacker during Friday's incident and said he had appeared calm and determined.
The man looked at him with "a lot of intensity and determination," Antoine said. "This was someone who was very precise in his movements, not panicked at all, someone who was in control."
French President Francois Hollande, speaking during a trip to Jerusalem, warned that the gunman "could still kill tomorrow or at any time."
Interior minister Valls said that everything possible would be done to apprehend the shooter.
"This individual is on the run and he represents a real danger. We will do everything we can to arrest him," he said.