Brazil on Tuesday declared three days of mourning for plane crash that killed at least 71 people in Colombia, Reuters reported on Wednesday. Brazilian football team Chapecoense was on board the flight. Colombian authorities said the crash took place in the municipality of La Union.

Six survivors were rescued from the crash site, including three Chapecoense players. Investigators flew from Brazil to La Union to join their Colombian counterparts. They will look through evidence from two of the plane’s black boxes to determine the cause of the crash. Bolivia and the United Kingdom also sent experts to help with the investigation.

The aircraft had reported facing electrical problems as well as poor weather conditions in the area before it crashed. However, no statement was issued regarding what caused the crash.

Chapecoense, part of Brazil’s first division, was heading to Medellin to play the Copa Sudamerica finals against Atletico Nacional. The tournament was suspended after news of the crash surfaced, with Atletico Nacional requesting that the championship trophy be handed to Chapecoense as a mark of respect, BBC reported. Other football clubs in Brazil offered their players on loan to the team and asked the sport’s governing body in the country to give it a three-year stay against relegation.

Local channels said the plane lost contact with ground staff while flying over North-West Colombia. It was identified as a chartered flight, RJ85 CP-2933, part of Lamia airline. It had taken off from Viru Viru International Airport in Santa Cruz de la Sierra, Bolivia and was on its way to Medellin airport.