UPDATED: 7:15 a.m. EST / 1:15 p.m. CET
As French authorities search for the two heavily armed brothers who attacked Charlie Hebdo, killing 12, the prime minister says the possibility of a new attack is their primary concern.
Early on Thursday, police closed in on a gas station in northern France after the two suspects, Cherif Kouachi, 34, and his brother, Said Kouachi, 32, were reportedly spotted there. There were reports that a service station has been sealed off as part of the investigation. However, French authorities have not confirmed this.
La station service de l'Aisne ou les suspects auraient été repérés a été bouclée #AFP pic.twitter.com/hPMtFQofFN— François Becker (@beckerin_AFP) January 8, 2015
Who are these men?
A third man, Mourad Hamyd, 18, surrendered at a police station in Charleville-Mézières, a small town in the eastern region, after learning his name was linked to the attacks in the news and social media, said Paris prosecutor's spokeswoman Agnes Thibault-Lecuivre.
French ambassador to Australia, Christophe Lecourtier at a press conference in Canberra, Australia, confirmed Mourad had been arrested. He also noted the 18-year-old suspect has a criminal history.
Earlier, police had issued a wanted poster for Cherif Kouachi, who was convicted on terrorism charges in 2008 and Said Kouachi. The Kouachi brothers were born to Algerian parents in Paris.
According to the wanted poster released early Thursday morning local time, the Kouachi brothers were presumed to be armed and dangerous.
France's prime minister, Manuel Valls, said the two men were known to intelligence services and the fear that they could carry out another attack "is our main concern." Valls told RTL radio there had been several detentions overnight during the manhunt.
Fusillade au sud de Paris: les deux blessés dans un état critique (source policière) pic.twitter.com/pr9COYw8EG #AFP— Agence France-Presse (@afpfr) January 8, 2015
A night of arrests for French police
As police hunted for the suspects, who wore masks during the deadly terror attack at the satirical newspaper's office in Paris, authorities raided an apartment in Reims, a city east of Paris in France's Champagne country.
Video from BFM-TV showed police dressed in white apparently taking samples inside an apartment. iTELE, a French news channel said authorities were searching for DNA samples and other evidence. It was not immediately clear who lived there.
Les policiers (vraisemblablement police scientifique) toujours présents dans l'appartement. pic.twitter.com/BCAHXfq7jn— Hugo Clément (@hugoclement) January 8, 2015
#Reims derrière ces policiers, l'appart au 1er étage perquisitionné. la +part des unités d'élite ont quitté la cité pic.twitter.com/zKoEaAv1Gk— Guillaume Auda (@GuillaumeAuda) January 8, 2015
Mood outside Reims block of flats is relaxed. Police commandos pulled back. Killer(s) not here if they ever were.— Jonathan Rugman (@jrug) January 8, 2015
The suspects, caught on tape by an eyewitness, shouted "Allahu akbar!" -- which translates to "God is great!" in Arabic -- as they walked outside Charlie Hebdo's office carrying large guns and dressed entirely in black. The magazine staff was in an editorial meeting, around lunchtime in Paris, when the gunmen opened fire.
One witness to the attack said the gunmen were so methodical he at first mistook them for an elite anti-terrorism squad.
Ten employees were killed, along with two police officers. Eleven others were wounded; four of those injuries are serious.
Charlie Hebdo has long been scorned by some Muslims because of its portrayal of the Prophet Muhammad. In 2011, the publication was firebombed after it ran a cartoon of the Prophet Muhammad.
An official who spoke to the Associated Press, on condition of anonymity because they weren't authorized to publicly discuss the sensitive and ongoing investigation, said the suspects were linked to a Yemeni terrorist network.
France raised its terror alert system to the maximum level — Attack Alert — and bolstered security with more than 800 extra soldiers to guard media offices, places of worship, transport and other sensitive areas.
Additional reporting by The Associated Press, Mashable staff.