Eleven newborn babies died in a hospital fire in the western Senegalese city of Tivaouane on Wednesday.
The fire at Mame Abdou Aziz Sy Dabakh Hospital was caused by "a short circuit", Senegalese politician Diop Sy said.
"The fire spread very quickly," he said.
The city's Mayor Demba Diop said "three babies were saved".
Senegal's President Macky Sall announced the deaths of the 11 infants late on Wednesday.
"I have just learnt with pain and dismay about the deaths of 11 newborn babies in the fire at the neonatal department of the public hospital," he said on Twitter.
"To their mothers and their families, I express my deepest sympathy."
Health Minister Abdoulaye Diouf Sarr, who was attending a meeting with the World Health Organisation in Geneva, said he would return to Senegal immediately.
"This situation is very unfortunate and extremely painful," he said on the radio. "An investigation is under way to see what happened."
The Mame Abdou Aziz Sy Dabakh Hospital was opened recently, local media reported.
The tragedy there comes after several other incidents at public health centres in Senegal, where there is a great disparity between urban and rural areas in healthcare services.
In the northern town of Linguere, four newborn babies were killed when a fire broke out at a hospital in April. City authorities said the cause was an electrical malfunction in an air-conditioning unit in the maternity ward.
Wednesday's blaze comes about a month after the nation mourned the death of a pregnant woman who waited in vain for a Caesarean section.
The woman, identified as Astou Sokhna, arrived at a hospital in the northern city of Louga in pain but staff refused her request for a Caesarean, saying it was not scheduled. She died 20 hours later on April 1.
Her death caused a wave of anger over the state of Senegal's public health system. Mr Sarr acknowledged two weeks later that the death could have been avoided.
Three midwives who were on duty the night Sokhna died were found guilty of "failure to assist a person in danger" and given six-moth suspended sentences by the High Court of Louga on May 11.
Amnesty International's Senegal director Seydi Gassama said his organisation had called for an inspection and upgrade for neonatology services in hospitals across Senegal after the "atrocious" death of the four babies in Linguere.
After the latest tragedy, Amnesty "urges the government to set up an independent commission of inquiry to determine responsibility and punish the culprits, no matter the level they are at in the state apparatus", he said on Twitter.
Opposition politician Mamadou Lamine Diallo also responded online with outrage to the Tivaouane blaze.
"More babies burnt in a public hospital … this is unacceptable @MackySall," he said.
"We suffer with the families to whom we offer our condolences. Enough is enough."