A boy has died after eating a poisoned Easter egg allegedly sent to his family by a woman who used to go out with his mother's boyfriend. Luís Fernando Rocha Silva, seven, died on Thursday (April 17) while his mum, Mirian Lira, 32, and sister Evelyn Fernanda, 13, remain in a serious condition in hospital.

Jordélia Pereira Barbosa, 35, was arrested in the city of Santa Inês in the Médio Mearim region of Brazil, according to local news outlet Maranhao.

The same publication reports Ms Pereira Barbosa was arrested on a bus by Maranhao's Civil Police along with officers from the SSP Intelligence Centre.

A motorcycle courier reportedly delivered the Easter egg to the family on Wednesday. It appeared as a gift from a secret admirer, bearing the message: "With love to Mirian Lira. Happy Easter".

Reports state Mirian later received a call from a woman who asked if the egg had been delivered. The caller failed to respond when Mirian asked who was on the other end of the phone.

Luís Fernando was the first to feel unwell. He was taken to Imperatriz Municipal Hospital where he was intubated to help him breathe. But he died just hours after being admitted.

Before his death, Luís Fernando's mum fell ill, with her hands turning purple and her breathing becoming laboured. She was admitted to intensive care at the hospital.

Evelyn Fernanda was then taken ill and admitted with the same symptoms. She too had eaten some of the Easter egg, according to local media.

In a statement, police said the case is being investigated as a priority and samples of the egg have been sent for analysis to the Imperatriz Criminalistics Institute to check for possible evidence of poisoning.