"National catastrophe"
 
Alaa Makki, the head of the parliamentary education committee, said both Shias and Sunnis had been abducted in the raid and he urged the government to respond rapidly to what he called a "national catastrophe".
 
Makki said some of the abducted men who were later released reported the armed group had had a list of names of those to be taken and claimed to be working for the government's anti-corruption body.
 
A female professor visiting at the time of the kidnappings said the abductors forced men and women into separate rooms, handcuffed the men, and loaded them aboard several pick-up trucks.
 
Abed Dhiab al-Ujaili, the minister of higher education, said: "We have no other option than to halt teaching in universities, at least in Baghdad, until we find out what happened.
 
"We are not ready to lose more professors."
 
Mass-kidnappings
 
Academics are increasingly being singled out in sectarian violence, and thousands of professors and researchers have fled the country.
 
At least 155 education workers have been killed since the war began and a university dean and a Sunni geologist were murdered recently.
 
The security forces have been accused of taking part in, or ignoring, several mass-kidnappings which are believed to have been carried out by sectarian groups.
 
The Sunni minority have blamed many of the kidnappings on armed groups from the now-dominant Shia parties, who control the interior ministry.
 
The higher education ministry is headed by a member of the main Sunni Arab political bloc.
 
Air raid protest
 
In Shula, a predominantly-Shia area of western Baghdad, mourners protested against what Iraqi officials said was a US raid that killed six people.
 
The US military declined to confirm there had been an operation in the neighbourhood.
 
Interior ministry sources said 13 people were also wounded after US troops called in an air strike when they came under fire from al-Mahdi Army fighters loyal to cleric Muqtada al-Sadr.
 
Angry mourners chanted slogans criticising the US and supporting al-Sadr.