A wildlife conservation group says large scale ivory seizures reached record highs in 2011 making it one of the worst years ever for elephants.

TRAFFIC, a group that tracks wildlife trading, says there were 13 large seizures this year totaling about 1,000 kilograms. The amount, which is more than double 2010's total, represents about 2,500 elephants.

Most of the illegal shipments of African elephant ivory are being sent to Asia for use in traditional medicine.

TRAFFIC's elephant expert Tom Milliken says the increase in ivory trade was caused by Asian crime syndicates operating in Africa.

Experts say the poaching has reached alarming levels in Congo, northern Mozambique, Tanzania and Kenya.

A global ban was placed on the ivory trade in 1989 in an effort to protect the animals. Africa's elephant population is estimated at around 600,000.