A woman has been arrested for allegedly trying to poison her child with cockroach bait in Matsolo, Nelspruit, Mpumalanga police said on Tuesday.

Superintendent Abie Khoabane said during the weekend police arrested the woman in connection with an incident where she allegedly gave her child poison diluted with water after suspecting the child's father of infidelity.

"On the evening of 28 April the woman woke her boyfriend, interrogating him about a missed call.

"The next morning the boyfriend (child's father) saw her throwing cockroach poison, mixed with tablets into a glass of water for the child to drink. He stopped her while she was giving the child the deadly concoction," said Khoabane.

She was in custody awaiting trial after appearing in the Matsolo Magistrate's Court on Monday on a charge of attempted murder.

The child has been placed in the care of family members.