Colombian rescuers found on Monday another three more bodies that were killed by a landslide Sunday in Antioquia department, in the northwest of Colombia, bringing the total deaths to 20, local authorities said.

The rescue workers have been working 24 hours non-stop, after a landslide on Sunday buried more than 100 people in the Medellin suburb of Bello, in Antioquia department.

Colombian Interior and Justice Minister German Vargas Lleras on Monday visited the affected area, together with Defense Minister Rodrigo Rivera and Environment Minister Beatriz Uribe.

After a meeting with local authorities, the Ministers declared the region a disaster area in order to gain access to more resources to aid the rescue operation.

So far, rescuers have not used any heavy machinery in the operation because "we are hoping that some people will still be alive," Vargas said.

Regional director of the Administrative Department for the Prevention and Attention to Disasters (Dapard) John Freddy Rendon told Xinhua that the rescue teams will continue their work, together with the Police and the National Army, even though "there is little hope of finding people alive."

Antioquia's governor Luis Alfredo Ramos said on Monday morning that there are an estimated 142 to 145 people buried by the landslide.

On Sunday night, he said to radio station Radio Caracol that the number of missing people could surpass 100 and the number of fatalities could also increase.

He said that the Red Cross and other rescue teams estimated that at least 145 people were missing due to the landslide.

Meanwhile, the Colombian government has sent a letter to all the diplomatic missions in Bogota to ask for international aid to help the country cope with the current rain season which is forecast to last until March.

The rains in Colombia, classified as the most intense rainfalls in the last 40 years, have killed 189 people and left almost 2 million homeless.