Forty-seven were injured and hospitalised at the Gen. Sani Abacha Specialist Hospital.
One of the deceased was identified as a female vigilance group member, who was screening the people entering the market. She was said to have died when the bomb went off.
The Medical Director of Gen. Sani Abacha Specialist Hospital, Dr. Garba Fika, told our correspondent that 19 people were confirmed dead and 47 injured.
He said two of the injured were undergoing surgery, while another two were referred to the Federal Medical Centre, Nguru for advanced medical care.
Police spokesman Toyin Gbadegesin said the explosive was triggered by a teenage girl.
The attack, according to an eyewitness, was orchestrated by a female suicide bomber, who detonated the explosive on her body.
The attack occurred about 9:30am at the popular Sunday Market.
Mohammed Ali, a vigilance group member in Damaturu, said the female bomber pretended to be queuing behind a truck pusher, who was being checked into the market and in the process, detonated the explosive, which killed the female vigilance group member, who was screening the people entering the market.
He dismissed a report that the bomber was a mentally-ill woman.
Red Cross and National Emergency Management Agency (NEMA) officials corroborated the casualty figure.
The Northeast Zonal Coordinator of NEMA, Mohammed Kanar, told our reporter in Damaturu that a combined team of Red Cross officials, NEMA and State Emergency Management Agency (SEMA) had evacuated bodies and taken the injured to the Gen. Sani Abacha Specialist Hospital.
An officer with the Explosive Ordinance Department (EOD) said five un-detonated explosives were recovered from the bag of the suicide bomber.
Governor Ibrahim Gaidam condemned the attack, describing it as callous, barbaric and unjustifiable.
In a statement by his Director of Press, Abdullahi Bego, the governor said free medical care would be given to the injured.