Mexico missing: Protesters block Acapulco airport
Thousands of Mexicans blocked the access to Acapulco airport on Monday in protest at the authorities' handling of the case of 43 missing students.
The demonstrators clashed with police and blocked the entrance to the airport for three hours.
Officials said on Friday that gang members had confessed to killing the 43 students and burning their remains.
Relatives say they will not believe they are dead until independent forensic tests confirm it.
Mexico's Attorney General Jesus Murillo Karam said the chances of ever identifying the remains retrieved from the site where the students were allegedly killed were slim.
He said that the remains were so badly burned that only two bones could be salvaged for DNA testing.
Mr Murillo Karam said they would be sent to a laboratory at the University of Innsbruck in Austria specialised in recovering DNA.
In the meantime, the 43 students still have the legal status of "disappeared".
The relatives of the missing have been highly critical of the way the investigation into the disappearance of the students has been handled.
The 43 went missing on 26 September after clashing with police in the town of Iguala, 200km (125 miles) south-west of the capital, Mexico City.
Municipal police officers have confessed to detaining them and later handing them over to a local drugs gang calling itself Guerreros Unidos (United Warriors).
On Friday, Mr Murillo Karam announced that three members of the gang had confessed to killing the students and setting their bodies alight.
The gang members allegedly told their leader that they thought the students were members of a rival gang.
"We incinerated them and threw them into the water. They're never going to find them," they are reported to have told their leader, who is also under arrest.
A search of the landfill site where the gang members reportedly carried out the killings yielded a number of plastic bags with human remains.
The disappearance of the 43 and the links it has revealed between the local authorities and the Guerreros Unidos have triggered mass protests.
Iguala Mayor Jose Luis Abarca is under arrest on suspicion of ordering police to intercept the students. Iguala's police chief is still on the run.
But residents say they suspect links between the gang and officials reach higher levels than that of the local town council.
The governor of the state of Guerrero, Angel Aguirre, resigned last month as pressure to find the students mounted.
Calls for President Enrique Pena Nieto to step down have also become more wide spread.
On Monday, protesters painted slogans such as "Pena Nieto, murderer" on the walls of the walls of Acapulco airport.
The president is in China attending the Asia-Pacific Economic Co-operation (Apec) summit, a trip which has furthered angered the relatives of the missing, who say they feel abandoned by the authorities.
Timeline: Iguala disappearances
26 Sept: Students from a teacher training college in Ayotzinapa travel to Iguala to protest and raise funds
Night of 26 Sept: Police stop the students, six people are shot dead, 43 students disappear
30 Sept: Iguala mayor Jose Luis Abarca asks for leave from his post, which is granted
4 Oct: Mass graves are found near Iguala containing 28 bodies, but forensic tests suggest they are not those of the students
19 Oct: Federal police are deployed to Iguala and replace the municipal force
22 Oct: Mexico's prosecutor general says an arrest warrant has been issued for Mr Abarca, his wife and the town's police chief
23 Oct: Guerrero state governor Angel Aguirre resigns
29 Oct: President Enrique Pena Nieto meets the relatives of the missing students and promises a "renewed search plan"
4 Nov: Mr Abarca and his wife are arrested in Mexico City
7 Nov: Three gang members confess to killing students and burning their bodies, according to Mexico's attorney general.