Investigators have recovered the cockpit voice recorder (CVR) from the crashed Air India flight, a key step in uncovering what caused last week's deadly accident.

The London-bound Air India aircraft, a Boeing 787-8 Dreamliner, crashed soon after taking off on Thursday from the western Indian city of Ahmedabad. At least 270 people have been killed, most of them passengers.

The CVR captures audio from the cockpit, including pilot conversations, alarms and ambient sounds.

The flight data recorder (FDR), which logs crucial flight parameters like altitude, speed and engine performance, had been recovered from the debris on Friday.

Both the CVR and FDR collectively form what is commonly known as the "black box" of a plane. It is a vital tool in air crash investigations, helping experts reconstruct the flight's final moments and determine the cause of the incident.

The black box, unlike the name suggests, is actually two bright orange devices - one for the CVR and the other for the FDR - painted with reflective strips for easier recovery after a crash. Both these devices are designed to survive a crash.

India's Aircraft Accident Investigation Bureau (AAIB) is leading the inquiry into the cause of the crash, helped by teams from the US and the UK.

On Sunday, officials from the US National Transportation Safety Board (NTSB) surveyed the site of the plane crash.

"The AAIB has launched a detailed investigation, and the US National Transportation Safety Board (NTSB) is conducting a parallel probe under international protocols, since the aircraft is American-made," a statement released on Sunday said.

Indian media outlets have reported, citing sources, that officials from Boeing and the Federal Aviation Administration (FAA) - the US aviation safety agency - also visited the site.

Separately, a high-level committee set up by the Indian government to examine the reasons behind the crash is expected to hold its first meeting on Monday.

The committee will submit a preliminary report within three months, the All India Radio said, and will propose new standard operating procedures (SOPs) to help prevent similar incidents in future.

As the investigation continues, families on the ground are still grappling with disbelief and trauma.

Less than a minute after taking off from Ahmedabad's Sardar Vallabhbhai Patel International Airport, the AI171 flight crashed into a doctors' accommodation building at the BJ Medical College and Civil Hospital.

All but one of the 242 passengers and crew members were killed. Officials have also been trying to establish how many people were killed on the ground and continuing the slow process of matching DNA samples to confirm the victims' identities.

Over the weekend, doctors said 270 bodies had been recovered from the site of the crash.

More than 90 victims have been identified through DNA matching, Dr Rajnish Patel of Ahmedabad's Civil Hospital said on Monday. He added that 47 of the identified bodies have been sent to their families.

Among the identified victims is Vijay Rupani, the former chief minister of Gujarat, whose funeral will be held on Monday. Rupani, whose political career spanned more than 50 years, will be laid to rest with full state honours in Rajkot city.

For many other families, the agonising wait continues.

Officials told the BBC that the identification process has been slow and painstaking, as many of the bodies were badly burned in the crash and are being processed in small batches.

Mistry Jignesh, waiting outside the hospital for updates on his niece, told the BBC on Saturday that officials told him that it might take longer for them to hand over his niece's remains as the search for bodies is still ongoing. He had earlier been told that the body would be handed over by Sunday, after the 72 hours it normally takes to complete DNA matching.

"When people are still missing, how can they complete the DNA process by tomorrow? What if my niece's remains haven't even been found? The wait is killing us," he said.