Mauritania's president, Mohamed Ould Abdel Aziz, was being flown to France for medical treatment after a bizarre incident in which he was shot in the stomach, apparently by mistake, by his own troops.
Authorities in the west African nation, regarded as a key ally in the battle against al-Qaida in the region, were insisting the shooting, which took place 25 miles (40km) outside the capital, was an accident.
The president appeared on state television from his hospital bed to call for calm. "I want to calm all citizens," Abdel Aziz said. "I want to reassure everyone about my state of health after this incident committed by error."
Sources say "jumpy" military guards at a checkpoint mistook Abdel Aziz, who was returning to the capital, Nouakchott, after a trip to the desert, for a security threat.
"Security forces have been on high alert for the last six days, jumpy, and were concerned that something might happen. Obviously this incident is very unfortunate," a diplomatic source told the Guardian.
"We believe the shooting was an accident," the source said. "The situation has now returned to normal – the international airports are open, and the virtual lockdown imposed after the incident has now been lifted."
The Mauritanian press reported the president spent more than eight hours at the military hospital in Nouakchott, where he was operated on by two doctors, and is being flown to France by a Moroccan air ambulance.
Reports say the military and presidential guard worked together to protect the president during the medical procedure, amid scenes of chaos on the streets.
The information minister, Hadi ould el-Mahjoub, said the president's injuries were not life threatening. "He was lightly wounded. He was able to get down from the car and walk without difficulty on his arrival at the hospital."
On Sunday morning, military checkpoints, which have been conducting routine searches and identity card checks around the capital for several weeks, were withdrawn.
Despite apparent calm in the capital, with markets open and ministries functioning as usual, questions remained about the incident, following initial reports that the shooting was a foiled coup attempt.
"There have been disgruntled middle-ranking soldiers who have been dealt with very swiftly by the regime," said a senior military source.
"There are a lot of questions going around. The question security is asking is why didn't the soldiers manning the checkpoints know the presidential convoy was passing. The president is always very heavily protected, his security detail is excellent."
Officials declined to comment on what happened to the soldiers at the checkpoint, or if anyone else in the convoy was hurt.
The shooting comes amid months of turbulence for Mauritania, which neighbours northern Mali – where al-Qaida-linked groups control vast swaths of territory – and which has been the subject of explicit threats by extremist groups.
Around 100,000 refugees from Mali have fled into Mauritania, which has a population of 3.5 million, placing additional strain on resources as the country struggles with a food crisis engulfing the Sahel region.
The country is also facing internal upheaval, with growing dissatisfaction with Abdel Aziz, who seized power in a military coup in 2008 before winning presidential elections a year later. Nouakchott has been the scene of opposition marches in recent months, with some commentators describing calls for Abdel Aziz to resign signs of a Mauritanian Arab spring.
"The official line is it was an accident but it's really not very clear at the moment what happened," a western diplomat said.