A plane carrying Algeria's ailing President Abdelaziz Bouteflika has landed near Algiers, state media say.
The 82-year-old leader spent two weeks in a hospital in Geneva. Since having a stroke in 2013 he has rarely been seen in public.
The president's plane flew to the Swiss city on Sunday before returning to Boufarik military airport, reports say.
Bouteflika's announcement that he would stand for re-election next month sparked huge protests across Algeria, BBC reported.
The demonstrations, which have seen tens of thousands of people take part, are thought to represent the biggest threat so far to Bouteflika's 20-year rule.
The plane had landed at Boufarik military airport in Algeria, according to media reports, which have not broadcast any footage of the flight.
Instead, it carried a live flight tracker map which showed the plane approaching Blida Province, where the airport is based.
The Algerian presidency later confirmed Bouteflika had returned after two weeks of "periodic medical checks" in Switzerland, state media APS reported.
The plane that was photographed in Geneva's Cointrin airport earlier on Sunday is thought to be the same one that flew him over on February 24.
Broadcaster Al Arabiya Hadath TV earlier reported that security forces had been deployed between Algiers airport and the presidential residence in Zeralda, just outside the capital Algiers.
Bouteflika's office previously insisted that he was just going to Geneva for routine health check-ups, but it led to speculation that his condition was far more serious.
He has said that the mass demonstrations, which broke out last month after he confirmed he would seek a fifth term, could plunge the country into "chaos".
Teachers and their students have gone on strike at several universities, with thousands taking part in protests on Sunday.
Algeria reportedly has more than 1.7 million students. More than a third of these live on campus, but many others travel long distances to study from family homes.
Thousands of students have spilled out into the streets of Algiers, waving the Algerian flag and chanting: "Bouteflika, there will be no fifth term."
Many shops in the city have been closed, and Reuters reports that train services have been suspended.
The student protests comes after demonstrations on Friday saw tens of thousands of people take part - possibly the biggest protests in the capital in 28 years.
On Friday, riot police fired tear gas to prevent the mostly peaceful groups from reaching a road leading to the presidential palace, and local reports said 195 people were detained by the security forces.
Many who demonstrated that day initially gathered at university sites before heading onto the streets.
What do the protesters want?
The wave of protests was triggered by the announcement last month that Bouteflika would seek a fifth term in office in April's election.
Bouteflika later released a statement saying that he would step down early if re-elected - but this has not placated the demonstrators.
Many young Algerians are frustrated by a lack of economic opportunity and by what they perceive as the corruption of an elite that has governed the country since it gained independence from France.