Four other people were killed, including a disaster agency official, after a house caught fire from the lava.
Authorities in Guatemala say 18 more people have been confirmed killed by a volcanic eruption, raising the death toll to 25.
Rescue workers are desparately battling to find missing people and pull bodies from the lava slicks, called pyroclastic flows, that engulfed the village of El Rodeo. The airport was also closed because of the danger that floating hot ash posed to aircraft.
Search and rescue operations for the missing and dead have been suspended due to low light and risky conditions, and will resume early on Monday morning, the spokesman said.
It is the second time the volcano has erupted this year, setting off loud explosions and spewing ash almost four miles into the sky.
A Reuters witness near the volcano said more people had been evacuated beyond a five-mile perimeter from the site after the latest explosion.
Just why they are so threatening can be seen from some of the eyewitness videos on YouTube of the Guatemalan eruption.More news: Whale Dies In Thailand After Swallowing 80 Plastic Bags
Volcan de Fuego, Spanish for "volcano of fire", exploded shortly after noon on Sunday. Numerous dead came from the three towns of El Rodeo, Alotenago and San Miguel los Lotes.
At least 15 people have been hospitalized, including 12 children, some of whom suffered severe burns, the health ministry said.
Videos posted on social media show the aftermath of the eruption.
Rescue operations were suspended until 5:00 A.M. (1100 GMT) due to risky conditions and inclement weather, said Cecilio Chacaj, a spokesman for the municipal firefighters department.
"As soon as we received the information around 6 a.m. that the volcano was in an eruptive phase, the protocol was initiated to verify with different sectors and also talk to the communities, to community leaders".
Aviation authorities closed Guatemala City's global airport because of the danger posed to planes, but the airport was reopened at mid-morning Monday after workers cleared away ash.
The volcano has registered a number of minor eruptions over the years, and no evacuations were ordered as scientific experts reported the activity was decreasing. People were seen covered in ash, fleeing the scene by foot.More news: At least 25 people killed by erupting volcano in Guatemala
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.
Guatemalan President Jimmy Morales said he would issue a declaration of a state of emergency to be approved by Congress and urged people to listen to warnings from emergency officials.
"They can travel further, as well as much faster, than lava flows".
Numerous deaths in Sunday's Volcano of Fire eruption in Guatemala were blamed on pyroclastic flows.
Hundreds of firefighters, police and soldiers are searching for the missing amid the still-smoking lava.
Dense ash blasted out by the volcano shut down Guatemala City's global airport, civil aviation officials said.More news: New Starbucks training manual promotes "becoming color brave"