Updated

The Benin president's doctor and his niece were a part of a failed plot to poison the leader of the West African nation by changing his medicine with something toxic, the state prosecutor said.

Prosecutor Justin Gbenameto said Tuesday that Dr. Ibrahim Mama Cisse, one of the president's nieces Zouberatou Kora and Former Minister of Trade Moudjaidou Soumanou have been charged with conspiracy and attempted murder. The three were arrested Sunday and have been in a civil prison in Cotonou since.

Gbenameto said that the niece and doctor were each promised payment of 1 billion CFA ($1.9 million) if they carried out the poisoning, and that a fourth person was involved in the plot, businessman Patrice Talon.

The plot to poison Benin President Boni Yayi, however, was foiled the president's niece had informed her sister who then told the president, the state prosecutor said.

The prosecutor said the plot was largely planned during the president's recent visit to Brussels, Belgium.

"The niece who accompanied President Boni Yayi during this trip would have been contacted and invited to the hotel where the businessman Patrice Talon was staying," he said, adding that Talon asked Kora to give her uncle the drugs through the physician.

"I will deliver an international arrest warrant against Mr. Patrice Talon. He must respond to his acts," said Gbenameto.

The prosecutor said they determined that Soumanou picked up drugs at the Cotonou airport on Oct.19, and gave them to Dr. Cisse.

The drugs from Soumanou are "drugs that the head of state usually takes but were this time substituted and replaced by toxic ingredients," according to the prosecutor's statement.

"The judge will decide what happens next," Gbenameto said.

The lawyer for Dr. Cisse and the former minister said, "We can't say under what conditions the statements were obtained and what was in those statements. I have not even been able to consult them."

"There is sufficient evidence to suggest that a plot may have existed, but we can't say by what side at this moment," said the lawyer Joseph Djogbenou.