Tasnim � Iran�s Foreign Ministry spokesperson expressed condolences to Congo over a fatal oil tanker collision that has killed at least 50 people in the Central African country.

In a message on Sunday, Bahram Qassemi voiced sympathy with the Congolese government and nation and families of victims of the deadly incident.

At least 50 people were killed and more than 100 sustained burns after an oil tanker collided with a bus on a highway in the west of the Democratic Republic of Congo on Saturday.

The accident occurred in the village of Mbuba, not far from Kisantu city and about 200km southwest of the capital, Kinshasa.

According to witnesses and officials, villagers had rushed to collect the leaking fuel when it caught fire.

The fire quickly spread to nearby homes, Congo's health ministry said in a statement. An investigation was under way into the cause of the accident.

Congo President Joseph Kabila has ordered three days of national mourning �in this particularly painful moment for the Congolese people.�