SANTIAGO XALITZINTLA, Mexico (AFP) - Mexico's Popocatepetl volcano has blown steam for days, prompting authorities to prepare for possible evacuations, but residents are used to their towering neighbour's rumblings and keep fearlessly heading to work.

Popocatepetl, which means "smoking mountain" in the Nahuatl language of the Aztecs, spewed more steam, gas and ash that rose three kilometres above the crater early Tuesday, according to the National Disaster Prevention Center.

National civil protection coordinator Luis Enrique Puentes said the volcano was "totally calm" following the eruption, which belched out glowing rocks.

While there was no immediate need to evacuate the population, the volcano could erupt again Wednesday, he added.

The volcano, which is 55km south-east of Mexico City, has also rumbled and spewed molten rocks in recent days. Last week, it covered several towns in ash, including the capital of Puebla state.

Authorities have raised the alert level to "Yellow Phase Three," the fifth of a seven-stage warning system, restricting access to an area of 12km around the volcano and preparing evacuation routes.

But people living in the nearby town of Santiago Xalitzintla appear calm despite the activity inside the 5,452m high volcano, known locally as "Gregorio" or "Don Goyo" and considered a magical rainmaker by indigenous populations.

"We go out, we look at it and we go back to sleep very soundly," said Guadalupe de Santiago, balancing a basket of candy on her head near a church in this town just 12km south of the volcano.

"(The volcano) takes care of us. Look at all the water he's sending us," she said as rain fell on her.

Hundreds of soldiers were sent to Santiago Xalitzintla and two other towns in case the volcano erupts and forces the evacuation of 11,000 residents in this area surrounded by corn fields and small cattle farms.

The soldiers checked the condition of roads in case they need to be used for an evacuation and the two shelters were set up in the state of Puebla to house 5,000 people.

Around 4.5 million people live within 50km of Popocatepetl, which had its last major eruption in 2000, forcing thousands of people to evacuate from surrounding towns.

But few residents evacuated in May 2012 when the volcano belched out ash, forcing the Puebla airport to close temporarily.

"We won't go to the shelter again if they tell us the same thing," Santiago said.

"Things got stolen from our house last year. All our animals were gone and nothing had happened up there," she said, pointing at the crater.

Every March 12, dozens of residents climb part of the volcano in an annual ceremony, leaving flowers, food and drinks as offerings to ask "Gregorio" to produce rain.

"We celebrate his birthday and ask him for rain and a good harvest," said Juan Garcia Agustin, the town's top official.

Agustin, who has checked the dirt roads that will be used in case of an evacuation, said residents would take shelter set up inside a school gym in the town of Cholula if necessary. Some 100 cots were ready, with bags on top of them filled with hygiene products.

But the shelter's doctor on duty, Juan Manuel Garcia, said residents are loath to evacuate.

"People are reluctant to leave their homes because experience tells them that nothing even happened before and that nothing will happen if they disobey evacuation orders," he said. "However, if they risk losing their animals and belongings, they'll listen."