Senegal said Monday it had implemented voluntary COVID-19 screening tests and reimposed the wearing of masks at Dakar's international airport for returning pilgrims fearing the virus was linked to the deaths of some Mecca pilgrims.

Dakar suspects that a number of the some 1,300 deaths — according to a Saudi tally — are down to a respiratory syndrome ailment such as COVID-19, Health Minister Ibrahima Sy said on Sunday.

"Initially, we thought it was related to heatwaves because the temperature was excessively high, but we realized that there is a respiratory syndrome with the cases of death," Sy said of the deaths during the hajj pilgrimage, which took place during intense heat.

"We told ourselves that, probably, there is a respiratory epidemic, and it was our duty to be able to monitor the pilgrims on their return by putting in place a screening system for everything COVID-19 related," said Sy in remarks carried by Senegalese broadcasters.

The health ministry said it had "strengthened the health surveillance system" by deploying a team at the airport to provide voluntary screening tests and identify pilgrims suffering from flu-like illnesses.

The ministry also urged the population "to be vigilant, to show restraint and to be more serene to avoid an epidemic."

Out of 124 rapid diagnostic tests, 78 proved positive for the COVID-19 virus, 36 of which were later confirmed by PCR tests, the ministry said.

Charles Bernard Sagna, chief medical officer for the airport, said the alert was raised when the Senegalese medical team based in Jeddah had reported "a significant number" of passengers with respiratory problems.

"There is no cause for alarm but there also has to be prevention," the ministry said Sunday.

Senegalese daily L'Observateur reported that five of the dead at the hajj were Senegalese nationals.

They were among an around 12,000-strong officially registered Senegalese contingent.

Saudi Arabia's official SPA news agency earlier reported 1,301 deaths at the annual hajj pilgrimage to Mecca, where temperatures climbed as high as 51.8 degrees Celsius (125 degrees Fahrenheit), according to the country's national meteorological center.

More than 80 percent of pilgrims attending mainly outdoor rituals were "unauthorized" and walked long distances in direct sunlight, according to SPA.

The hajj is one of the five pillars of Islam that all Muslims with the means must complete at least once in their lives.

Saudi officials have said 1.8 million pilgrims took part this year, a similar number to last year, and that 1.6 million came from abroad.