A Nigerian journalist who claims to have access to the Boko Haram leadership fears that only around 30 of the 113 missing Chibok girls are still alive, something the Nigerian government refutes.

In a series of tweets on Saturday, Ahmad Salkida said he feared most of the missing girls had died in captivity. The journalist initially said that only 15 out of 113 had survived, but he later claimed that 10 more girls were being held elsewhere and that there are five more who are said to be alive.

"A leading member of the Jama'atu Ahlis-Sunna Lidda'Awati Wal-Jihad or BH has now clarified the earlier information about 15 girls. Indeed, the 15 #Chibokgirls are available, but known to a particular cell that spoke to me emphatically days leading to the 4th anniversary," he tweeted.

"However, two other cells within the larger group has brought additional information, clarifying the earlier information, that there is another 10 girls available to another cell. Outside of the 15 and 10, another 5 amongst the girls are also alive as at early hours of today," he stated in another tweet.

Salkida claimed that five of the surviving girls had been indoctrinated by Boko Haram and had asked not to be included among those who would be released in the future.

The journalist explained that he posted the tweets marking the fourth year anniversary of the kidnappings to stir debate and compel the government and Boko Haram to release more information about the Chibok girls. He also said he wanted to ensure that the girls' parents had updated and accurate information.

The federal government responded to Salkida's tweets by saying it has information that all the remaining Chibok girls in captivity are still alive.

Salkida's tweets came just after parents of the missing girls and their supporters took part in a vigil and a protest to mark the anniversary of the kidnappings. His claims have resulted in calls for proof of life to establish exactly how many of the girls are still alive.

Boko Haram kidnapped a total of 276 girls from the Government Girls Secondary School in Chibok on April 14, 2014. Later, 57 girls were able to escape and at least 107 were found or released as part of negotiations between the militants and the government.

In August 2016, Boko Haram released a video showing 50 of the missing girls, while claiming that there were some who died from air strikes.

Ayuba Alamson Chibok, a community leader in the town, said he had spoken to some of the girls who were released and that they had confirmed to him that there were some who died in a military strike, according to Agence France Presse.

He said the girls were only able to confirm 11 fatalities and said there was "no way of knowing" if more had been killed in other military operations since that time. He is urging Boko Haram to release a "proof of life" video for the remaining Chibok girls.

Alamson, who has a cousin among the missing girls, said that the latest claim by Salkida was alarming, and he urged the government in Abuja to immediately gather more information about the situation.

"This claim has added to the grief of parents. The government should act fast. The longer it takes to resolve this issue, the more the future of these girls is destroyed," he said according to Agence France Presse.