Fire crews battle a blaze aboard a Mexican tanker in the Gulf of Mexico, September 2016. Mexican navy

A fire aboard a Mexican oil tanker in the Gulf of Mexico was put out late Sunday, but about 100 emergency personnel are still monitoring the stricken vessel, according to AFP.

The tanker, the Burgos, erupted in flames around midday on Saturday when it was about 7 miles from the coast of southeastern Veracruz state.

Initial reports suggested the blaze was caused by an explosion, but subsequent reports indicate the cause is still unknown. The 31 crew members aboard the tanker were evacuated safely.

The Burgos was carrying about 168,000 barrels of gasoline and diesel fuel, and while some of the fuel was washed into the ocean by water used to fight the fire, Mexican authorities denied that there had been environmental damage or spills in the Gulf.

The ship "has a double hull that prevents the fuel it carries from being spilled," state oil company Pemex CEO Jose Antonio Anaya told a press conference.

Earlier, navy firefighting official Antonio Chedraui reported that there was fire on the water, "a sign that the fuel is leaking," according to AFP. Pemex said on Sunday that fuel seen on the water would dissipate.

A Mexican sailor looks over the tanker Burgos as it burns in the Gulf of Mexico, September 2016. Mexican navy

Crews from Pemex, the Mexican navy, and elsewhere fought the flames on Saturday and Sunday, with equipment and personnel arriving from around Mexico. Pemex also worked with fire-control advisers from Houston, Texas.

About 70,000 liters of foaming liquid were deployed and 10,500 feet of containment barrier were prepared in case fuel had spilled into the sea, according to Anaya.

Chedraui also said it took four hours to get special fire-retardant foam to the location of the burning ship, and that Pemex was slow in setting up floating containment barriers to prevent the spill from spreading, according to AFP.

The Burgos was one of the oldest ships in Pemex's fleet and one of 17 tanker-type vessels the state oil company uses to transport fuel in the Gulf of Mexico and the Pacific.

Photos in the tweet below show the Burgos from above:

—Luis Alberto Fuentes (@jaliscoesuno) September 26, 2016

The fire follows a series of other mishaps at Pemex, which is coping with major losses, increased competition at home, sharp budget cuts, and lower revenue due to the oil-price rout, according to Reuters.

On land, the state oil company has had to deal with rampant oil theft from pipelines throughout the country by both criminal groups and regular people.

While no deaths have been reported, Pemex has experienced fatal incidents in the recent past, Reuters noted.

In April, more than 30 people died and dozens were injured in an explosion at a petrochemical plant in southeast Veracruz state, a joint venture between Pemex and another firm.

In 2013, at least 37 people were killed by a blast at Pemex's Mexico City headquarters, and 26 people died in a fire at a Pemex natural-gas facility in northern Mexico in 2012.

A 2015 fire at a Pemex platform in the Bay of Campeche affected oil output and cost the company up to $780 million.