(CNN) -- Militants on Tuesday seized the airport, TV stations and governor's offices in Mosul, Iraq's second-largest city, as police and soldiers ran from their posts -- a stunning collapse of the security forces that has raised questions about Prime Minister Nuri al-Maliki's ability to hold the country together.
In perhaps a sign of just how serious the threat is to Iraq's stability, al-Maliki took to the airwaves to call on all men to volunteer to fight, promising to provide weapons and equipment.
"We will not allow for the remainder of the ... province and the city to fall," he said in a live speech broadcast on Iraqi state TV.
The militants are believed to belong to the extremist group the Islamic State in Iraq and Syria, an al Qaeda splinter group also known by its acronym ISIS. These fighters are believed to include many from outside Iraq, senior police officials said.
Mosul wasn't the only place in the country beset by violence Tuesday, including some focused closer to the capital of Baghdad. Still, what's happening in this northern Iraqi city the most serious, given its size, the bloodshed's scope, and the major humanitarian situation tied to it.
Already, hundreds on Mosul have been killed since the fighting began five days ago. Tens of thousands more have fled in vehicles and on foot, some of them carrying only what they could in plastic bags. This rush has contributed to bottlenecks at checkpoints as people tried to get to safety in nearby Erbil.
Within Mosul, militants managed to take control of security checkpoints, military bases and a prison, where they freed up to 1,000 prisoners, authorities said.
A Reuters journalist on the ground in Mosul reported seeing policemen take off their uniforms and drop their weapons.
The bodies of members of Iraqi security forces, some mutilated, littered the streets, the journalist reported.
"We can't beat them. We can't. They are well-trained in street fighting, and we're not. We need a whole army to drive them out of Mosul," one officer, whose identity was withheld, told Reuters.
A journalist with Agence France-Presse, who was fleeing the city with his family, reported security forces had abandoned vehiclesand a police station was set on fire.
Al-Maliki urged parliament to declare a state of emergency.
"This requires all efforts, both civilian and official, to confront this ferocious attack that harms all Iraqis, from a deteriorating security situation to a humanitarian crisis," he said in his televised speech.
Fighting elsewhere around Iraq
Political and sectarian violence have wracked Iraq for months, often pitting minority Sunnis against majority Shiite Muslims, who came to dominate the government after Iraqi leader Saddam Hussein was overthrown in 2003.
Tensions are fueled by widespread discontent among the Sunnis, who say they are marginalized by the Shiite-led government and unfairly targeted by heavy-handed security tactics.
Militants also believed to be from ISIS have also taken control of two villages in Kirkuk province and one in Salaheddin province, Iraqi police officials told CNN on Tuesday.
The move into Salaheddin province -- the capital of which, Tikrit, was Hussein's hometown -- shows how close the major fighting is getting to Baghdad.
On Tuesday night, for instance, Iraqi security forces were clashing with dozens of gunmen attempting to storm the Baiji oil refinery about 200 kilometers (125 miles) north of the capital, police officials in Tikrit said.
Closer to Baghdad, at least 31 people were killed and 28 others injured in a series of roadside bombs detonated at a cemetery on the outskirts of the central city of Baquba, according to police officials.
This violence is not new to Iraq. Deaths were common in the years after Hussein's capture over a decade ago, though the Iraqi government had help from U.S.-led forces at that time.
Yet, after a brief lull, the bloodshed has picked up. The United Nations has said 2013 was the deadliest year in Iraq since 2008, with more than 8,800 people killed -- most of them civilians.
Conflicts starting everywhere. This really gives grim pictue to entire war. Imagine if the ISIS reach Saudi and Kuwait border,USA would probably get involved once again. We really live in little too interesting times.