A Sudanese woman freed from death row yesterday has reportedly been arrested with her husband as they tried to leave the country with their children.

A court ordered the release of Meriam Ibrahim (27) on Monday after she was imprisoned for converting from Islam to Christianity.

The government said she was released after "unprecedented" international pressure.

A security source said Ms. Ibrahim and her husband, Daniel Wani, were detained as they tried to board a plane at Khartoum Airport.

"The National Security took her and Daniel" said the source.

He could not give more details except to say they were taken to a facility used by the powerful National Intelligence and Security Service (NISS).

"She has the right to leave the country" the source said. The status of their two young children - one a newborn baby - was not immediately known.

Ms. Ibrahim was convicted last month of apostasy and adultery and claimed she had always been a Christian, having been raised by her Ethiopian mother while her Muslim father had left when she was young.

She married Mr. Wani in 2011 and has refused to renounce her faith.

Ms. Ibrahim was forced to give birth to her second child, a daughter called Maya, in prison. Her son, Martin, also lived in prison with her.

Earlier this month there was international condemnation of the mother's plight.

Sudan introduced Islamic Shariah law in the early 1980s under the rule of autocrat Jaafar Nimeiri, a move that contributed to the resumption of an insurgency in the mostly animist and Christian south of Sudan.

The south seceded in 2011 to become the world's newest nation, South Sudan.