MEXICO CITY - International experts for the Inter-American Human Rights Commission say they are running into serious obstacles in their probe of 43 students who went missing in southern Mexico in 2014.

The experts told a Sunday news conference they were concerned about their limited access they are being given to new information in separate official files as well as leaks of statements by some people held in the case "that don't respond to the truth."

In their first report, in September 2015, the experts rejected the official version that said the students' bodies had been incinerated at a dump. They also alleged some authorities had obstructed justice in the case.

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The students from a local teachers' college went missing on Sept. 26, 2014, after clashing with municipal police in Guerrero state.