Nigeria's President Goodluck Jonathan on Friday cancelled a visit to the hometown of more than 200 schoolgirls who were kidnapped by Islamic militants, sparking fresh criticism of his handling of the crisis.
A senior government official told AFP that Jonathan's trip to remote Chibok in Borno state "was on (the president's) schedule up to this morning" but the visit had been scrapped.
No reason was given but security concerns were reportedly blamed.
Instead of visiting Chibok, Jonathan is now due to head direct to a security summit in Paris on Saturday to discuss the Boko Haram threat to regional stability.
Jonathan's administration has been widely criticized for its slow response to the kidnapping on April 14, which saw 276 girls abducted by militants. A total of 223 are still missing.
But they were forced to act in the face of a social media campaign and street protests that won global support and attracted the attention of foreign powers, who have now sent specialist teams to help in the rescue effort.
The cancellation prompted immediate criticism on social networks and others who claim the president has shown indifference to the mass abduction.
"If, as the commander-in-chief of the armed forces, he is afraid to visit Chibok because of security fears, he is simply telling the hapless people in the northeast that he cannot protect them and they should resign themselves to their fate," said Debo Adeniran, of the Coalition Against Corrupt Leaders pressure group.
In the United States, which has sent drones and surveillance aircraft, the chairman of the Senate Committee on Foreign Relations said Nigeria had been "tragically and unacceptably slow" to tackle the crisis.
"I have called on President (Goodluck) Jonathan to demonstrate the leadership his nation is demanding," Democratic senator Robert Menendez said.
Others raised the Nigerian military's human rights record after well-documented claims of abuses carried out by soldiers, including arbitrary detention and summary execution of civilians.
The Principal Deputy Assistant Secretary of State for African Affairs, Robert Jackson, told senators: "Resolving this crisis is now one of the highest priorities of the US government."
A state of emergency was imposed in three northeastern states worst affected by the violence on May 14 last year. Special powers were extended for a further six months in November.
Jonathan requested the extension on Tuesday, calling the security situation in Borno, Yobe and Adamawa "daunting."
More than 2,000 have been killed this year alone, most of them civilians, in increasing violence across Muslim-majority northern Nigeria that has seen churches, schools and entire villages attacked.
Police in northern Bauchi state said about 30 gunmen destroyed two village primary schools late on Wednesday but no one was injured.
The lower House of Representatives has voted unanimously for an extension, while senators are expected to vote Tuesday. A two-thirds majority is required from both chambers.
The governor of Yobe has come out against any extension and his counterparts in Borno and Adamawa are likely to follow suit.
All three are members of the main opposition party.
Initial gains from the state of emergency in forcing Boko Haram out of urban centers appeared to have been lost, with questions raised about the military's tactics and ability to curb the threat.
Disgruntled troops on Tuesday fired shots into the air when the local commander paid a visit to the state capital of Borno, Maiduguri to sympathize with them after a Boko Haram ambush killed some of their comrades.
Six soldiers, including one officer, were killed as they returned from patrol duties in Chibok, the defense ministry said, adding that the commander was not injured by the firing.
Jonathan has ruled out a prisoner swap with the extremists after Boko Haram leader Abubakar Shekau mooted the possibility in a video released on Monday showing the kidnapped schoolgirls.
But the government said it remained open to wider talks on ending the insurgency.
Relatives of the missing girls have called for their unconditional release.
"For me, I want these girls released without any negotiations," said Ayuba Chibok, whose niece is among the hostages.
"Even if Boko Haram wants to request something from the government, let them request something else," he told AFP by telephone.
"Let (Shekau) release these girls unconditionally."
With US, British, French and Israeli teams on the ground helping the Nigerians, the battle against Boko Haram spread to Sudan, where one of the alleged masterminds of an April 14 bombing in Abuja was arrested.
Army deserter Aminu Sadiq Ogwuche, who served in a Nigerian intelligence unit, was held on suspicion of involvement in the car bomb attack on a bus station that killed at least 75 as he tried to obtain a Turkish visa in central Khartoum.
Ogwuche arrived in Khartoum late last year to study Arabic at the International University of Africa but visited Nigeria earlier this year, a source familiar with the case said.