GUATEMALA CITY: One of Central America's most active volcanos erupted in fiery explosions of ash and molten rock Sunday, killing at least seven people and injuring 20 while a towering cloud of smoke blanketed nearby villages in heavy ash. An undetermined number were missing, and authorities feared the toll could rise.

Guatemala's Volcan de Fuego, Spanish for "volcano of fire," exploded shortly before noon, and later in the afternoon lava began flowing down the side of the mountain. Eddy Sanchez, director of the country's seismology and volcanology institute, said the flows reached temperatures of about 1,300 degrees Fahrenheit (700 Celsius).

Video images published by Sacatepezuez television showed a charred landscape where a lava flow came into contact with homes. Three bodies lay partially buried in ash-colored debris from the Volcan de Fuego, Spanish for "volcano of fire," about 27 miles (44 kilometers) from Guatemala City.

Other videos from local media showed residents walking barefoot and covered in muddy residue.

"Not everyone was able to get out. I think they ended up buried," Consuelo Hernandez, a resident of the village of El Rodeo, told the newspaper Diario de Centroamerica.

"Where we saw the lava fall, we ran to a hillside" to escape, she added.

Hundreds of rescue workers, including firefighters, police and soldiers worked to recover bodies from the still-smoking lava.

National Disaster Coordinator Sergio Cabanas said seven people were confirmed dead and an unknown number were unaccounted for.

Among the fatalities were four people, including a disaster agency official, killed when lava set a house on fire in El Rodeo village, Cabanas said. Two children were burned to death as they watched the volcano's second eruption this year from a bridge, he added.

Another victim was found in the streets of El Rodeo by volunteer firefighters, but the person died in an ambulance.

Guatemala's disaster agency said 3,100 people had evacuated nearby communities, and the eruption was affecting an area with a population of about 1.7 million people. Shelters were opened for those forced to flee.

Ash was falling on the Guatemala City area as well as the departments of Sacatepequez, Chimaltenango and Escuintla, which are in south-central Guatemala around the volcano. Streets and houses were covered in the colonial town of Antigua, a popular tourist destination.

Aviation authorities closed the capital's international airport because of the danger posed to planes by the ash.

The conical Volcan de Fuego reaches an altitude of 12,346 feet (3,763 meters) above sea level at its peak.