Families of those who died in the June Air India crash near Ahmedabad have called for the immediate release of the aircraft’s flight recorders, expressing frustration that delays are undermining confidence in the probe.

The Boeing 787 Dreamliner, carrying 241 passengers, crashed shortly after takeoff, killing everyone on board as well as 19 people on the ground.

A preliminary report from India’s Aircraft Accident Investigation Bureau revealed that fuel supply to the plane’s engines was cut off moments before the crash.

While the report stopped short of assigning blame, it included cockpit voice recordings suggesting confusion between the pilots. One pilot asked the other why the fuel had been cut off, and the second replied that he had not done so.

“We are formally demanding the immediate release of the Cockpit Voice Recorder and Flight Data Recorder,  the black box,” said Imtiaz Ali Sayed, who lost his younger brother, sister-in-law, and their two children in the accident. Speaking on behalf of 60 grieving families, he stressed the importance of the devices in uncovering the truth behind the tragedy.

“These devices contain vital information that can reveal the truth behind this horrific tragedy,” Sayed said in a statement. He added, “Every day without answers deepens the pain of our loss and erodes public trust in aviation safety.”

Some families are considering legal action against Air India and Boeing, the aircraft’s manufacturer in the US, according to their lawyer.

Mike Andrews, from the Beasley Allen Law Firm representing 65 families from India and the UK, met with relatives in Vadodara city, south of Ahmedabad, on Friday after visiting the crash site.

“If the flight data recorder and cockpit voice recorder indicate that there is a defect with the aircraft... in that case, the options are to bring a defective product or a product liability claim in the United States for those claims,” Andrews told reporters.