One bomb was hidden in a coffin in the courtyard of the mosque and another in a shoe cabinet at the entrance, the source added.
At least one person was killed and 62 wounded, according to a spokeswoman for the city's Al-Jala hospital, Fadia al- Barghathi.
The blast follows twin car bombings on January 24 outside a mosque in Benghazi that left nearly 40 people dead.
There was no claim of responsibility for that attack, which underscored the ongoing chaos in the Benghazi region which is controlled by the forces of military strongman Khalifa Haftar.
Haftar, who opposes a UN-backed unity government based in Tripoli, announced Benghazi's "liberation" from jihadists in July last year after a three-year campaign, but sporadic violence has continued.
Libya has been wracked by violence and divisions since dictator Moamer Kadhafi was toppled and killed in a 2011 NATO-backed uprising.
On September 11, 2012, suspected jihadists linked to Al- Qaeda attacked the US consulate in Benghazi, killing ambassador Christopher Stevens and three other Americans.
(This story has not been edited by Business Standard staff and is auto-generated from a syndicated feed.)
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