MONTEVIDEO – Striking sanitation workers have decided to return to work in Montevideo to avoid penalties, including possible firings, Uruguayan union spokesmen said Sunday.

More than 7,000 tons of trash have piled up in the capital since sanitation workers walked off the job several weeks ago.

The sanitation workers plan to go back to work at midnight in the capital, where about half of Uruguay’s 3.4 million people live.

The decision to go back on the job was made “to avoid having the comrades who collect the trash face the possibility of penalties,” ADEOM municipal workers union official Walter Diaz said.

The union has staged staggered strikes in the past month that affected trash collection and other services.

The strike’s biggest effect was the accumulation of mountains of trash on the streets of Montevideo, posing a threat to the public health.

Leftist President Jose Mujica’s administration declared trash collection an “essential service” last Thursday, limiting workers’ right to strike and forcing union members to return to work.

The union initially rejected the government decision and threatened to extend the strike until the middle of this week.

Union officials later changed their position in light of the possibility that strikers might be fired.

The union was demanding a minimum salary of 20,000 pesos (about $1,000) a month and more investment in municipal services.

The government deployed army troops Saturday to collect the trash from 76 large dumps established in recent weeks.

About one-quarter of the garbage was gathered on the first day of work and “several more days will be needed to collect the accumulated tons of trash,” the Defense Ministry said.

The Montevideo city government also hired private contractors to pick up trash around the city.