LAGOS, Nigeria — Four young men were convicted of gay sex and whipped publicly as punishment Thursday in an Islamic court in northern Nigeria, a human rights activist said.

The four were among dozens caught in a wave of arrests after Nigeria strengthened its criminal penalties for homosexuality with the new Same Sex Marriage Prohibition Act in January.

The men could face further violence in prison if human rights organizations do not come up with an additional fine of $120 each meted out Thursday by a judge in Bauchi city, Dorothy Aken’Ova, convenor of the Coalition for the Defense of Sexual Rights Network, told The Associated Press.

The four were sentenced to 15 strokes plus a year’s imprisonment if they cannot pay their fines.