The government has linked the abduction of the security officers to "armed bandits", a term used to refer to Tuareg fighters, who have previously launched attacks against the government.
Coulibaly said that it had been years since a vehicle had hit a mine in the region.
In a separate incident on Thursday, one soldier was killed and several were injured when their vehicle hit a mine, an officer said on condition of anonymity.
The landmine blasts come a day after a military convoy was ambushed in the Tinzaouaten area by suspected Tuareg fighters.
"It is a heavy toll - five Toyota pickups taken, others burned or disappeared, dozens of soldiers scattered and many missing, including a lieutenant who may have been captured," said one military source, who asked not to be identified.
On Monday, a military convoy travelling between the northern towns of Kidal and Tinzaouaten was attacked and 15 soldiers were taken hostage, a day after 24 hostages were taken in Tidjeret.
A military patrol was able to recover nine of those taken captive on Wednesday when they were abandoned by fighters heading toward Mali's border with Niger.
Though Mali is often called one of the most stable countries in West Africa, its northeastern desert region was the focal point for a 1990s Tuareg armed campaign against the government.
Fighting between armed Tuaregs and army soldiers re-erupted last year.
The attacks this week occurred near the border with Niger, whose government has also faced opposition from Tuareg fighters since early this year.
In recent years, Tuaregs in Mali have accused the government of failing to develop the country's poor northern region.
A peace deal was signed after last year's fighting, which called for the government to develop three regions in the north in exchange for Tuareg fighters dropping demands for autonomy.
Newspapers in Mali have identified Ibrahim Bahanga, a Tuareg fighter who denounced the peace deal, as behind the recent attacks.
Bahanga is accused by Malian authorities of killing a police officer in an attack in May.
An associate of Bahanga said recently that his group was seeking an alliance with the Niger Movement for Justice (MNJ), the Tuareg fighters in Niger.
Seydou Kaocen Maiga, the MNJ's Paris-based spokesman, denied that the group had formed an alliance with Bahanga.
"We are all Tuaregs. The Tuaregs in Mali are our cousins, our family. But that doesn't mean we have a military alliance with them," he said.
The majority of Mali's Tuareg former fighters have condemned the new attacks.
Last week, Mali and Niger's security ministers met in the eastern Malian town of Gao to sign a deal which allows security forces from both countries to pursue suspected fighters across their border.