Bamako - President Ibrahim Boubacar Keita warned on Monday that "odious crimes" that have left more than 30 people dead in northern Mali would not go unpunished even as Tuareg rebels released civil servants taken hostage in a deadly siege at government offices there.
The release of the hostages came as 1 500 Malian troops poured into the town of Kidal, sent to restore government control in the bastion of Mali's Tuareg separatist movement, 1 500km northeast of the capital.
A firefight between the army and separatists from the National Movement for the Liberation of Azawad (MNLA) outside the regional governor's headquarters on Saturday had left eight soldiers and 28 insurgents dead.
The rebels seized the governor's office and took the civil servants hostage.
"After negotiations that took place during the night of Sunday May 18 and Monday May 19, MINUSMA recovered 32 prisoners from the MNLA and transported them to the MINUSMA camp in Kidal where a medical check-up was offered," the United Nations' MINUSMA peacekeeping force said.
"MINUSMA will ensure their transport back to Bamako as soon as possible."
Meanwhile a foreign military source told AFP that "1 500 Malian soldiers arrived in Kidal in the last 24 hours. They are continuing to come.
Crimes against humanity
"They have come with weapons and luggage, many people and many weapons".
A defence ministry official confirmed the information, saying the figure was set to rise.
"Our soldiers will defend the country, by force, if necessary," he added.
In a message on public ORTM television Keita said visiting Prime Minister Moussa Mara and several government ministers had been "received (in Kidal) with heavy gunfire by armed groups".
"I swear that these odious crimes will not go unpunished ... They are crimes against humanity."
He added: "The perpetrators of the hostage-takings and mass executions will be prosecuted by national and international courts."
Mara, who was in Kidal over the weekend as part of a first visit to the restive north since his appointment, said Sunday that terrorists had "declared war on Mali".
"We will mobilise the resources to fight this war," Mara told AFP by telephone.
The Malian government has blamed the clashes on Tuareg separatists but Mara said Islamist militants had taken advantage of the crisis "to participate in the chaos alongside other terrorist groups".
He said before the hostage release that some of those kidnapped had been "killed in cold blood" while others were freed as they had been wounded.
The MNLA had said the regional director of Kidal was among the hostages, along with a prefect, the governor's adviser and 24 soldiers.
Mara said the governor's offices had been attacked by "jihadists, terrorists... with the clear aim to destroy and kill".
Malian troops "reacted accordingly. Today Malian armed forces are in Kidal, (they) are readying themselves for any contingencies," he said.
Defence Minister Soumeylou Boubeye Maiga identified the rebels on Sunday as members of the MNLA, who he said were "supported by members of terrorist groups".
"Our forces have taken control of all government buildings except, for the moment, the governor's offices," he said.
Foreign troops criticised
Following a June peace deal that paved the way for presidential elections, the Tuareg separatists evacuated the governor's offices in November last year after a nine-month occupation.
But the process deeply divided the MNLA, whose ultimate goal is the independence of Azawad, the minority Tuareg name for their homeland in northern Mali.
Up until the agreement, the Tuareg group had refused to allow any government soldiers or civil servants into the desert town.
The country descended into crisis in January 2012, when the MNLA launched the latest in a string of Tuareg insurgencies in the north.
A subsequent coup in Bamako led to chaos, and militants linked to al-Qaeda overpowered the Tuareg to seize control of Mali's northern half.
A French-led military operation launched in January 2013 ousted the extremists, but sporadic attacks have continued, and the Tuareg demand for autonomy has not been resolved.
Foreign troops in Mali have come in for some criticism since Saturday, with Twitter users wondering under the #MINUSMerde hashtag why peacekeepers had seemed unable to repel the rebels.
"We demand that you leave Kidal. Your agenda is not that of Mali. We refuse the de facto partition of the country," a tweeter identifying himself as an architect named Harouna Traore said.
At a protest in Gao, Mali's largest northern town, demonstrators in their hundreds chanted "down with MINUSMA" and "Free Kidal", witnesses told AFP.