Madagascar's government on Wednesday announced an international probe into allegations of rights abuses by its security forces during a recent crackdown on cattle-rustling gangs.

"Joint investigations will be carried out by the government and the international community so that there won't be doubts and questions about what happened there," Prime Minister Omer Beriziky's office said in a statement.

The United Nations will be involved in the inquiry, according to Oumar Kane, a representative of the Office of the United Nations High Commissioner for Human Rights.

Amnesty International last week accused Madagascar's military of killing dozens of people including children, the elderly and the physically disabled during a two-month operation to smoke out cattle thieves from villages in the south of the island.

Witnesses told the rights group that the security forces had executed suspects on the spot, including one physically disabled person and the parents and wife of a high-profile suspect.

During the many raids nearly 100 village homes were razed in one district while 11 villagers, including a six-year-old, were killed.

The London-based rights group expressed concern about the impact of the violence on security in the region, ahead of presidential elections planned for May 2013.

The rampant theft of cattle evolved from a customary practice in which a youth must steal an animal to prove his manhood and win the favour of his in-laws.

But the rustling escalated this year, fuelled by a growing market.