Experts claim the government is limiting their access to new information, including videos, about the 43 teaching students who disappeared in 2014

International experts for the Inter-American Human Rights Commission have said they have run into serious obstacles in their investigation of the case of 43 college students who went missing after being detained by police in southern Mexico in 2014.

Members of the panel said at a news conference on Sunday they were concerned about being given limited access to new information uncovered by government investigators and criticised leaks of statements from some of those arrested in the case that the panel said “don’t correspond to the truth”.

One year ago, 43 Mexican students were killed. Still, there are no answers for their families Read more

They also said authorities had not allowed them be present for statements by military personnel who were witnesses to the disappearance or had been given access to videos that could clarify what happened that night.

In response to the complaints, the federal attorney general’s office issued a statement reaffirming its willingness to work with the panel and said it already was investigating the leaks. It denied officials fragmented findings from the government’s investigation, which it said remained open.

In their first report in September, the expert panel rejected the official version of the government that, after being killed, the students’ bodies were incinerated at a dump. The panel alleged at that time that some Mexican authorities had obstructed justice in the case.

The students from a local teachers college have not been seen since 26 September 2014, when they were detained after clashing with municipal police in the city of Iguala in Guerrero state. Six other people were killed during the clashes, including some not involved in the confrontation.

Government prosecutors have said the police turned the students over to a local drug gang, which killed them and burned their bodies.