GAUHATI, India (AP) — Forest guards were attempting to catch a rare rhinoceros that was shot and dehorned by poachers after it wandered out of a flooded national park in northeastern India yesterday, in the fourth such attack in two days, a state official said.

The guards, joined by dozens of villagers, were chasing the injured rhino in the Jagdamba Tea Estate near the Kuthori forested area in Assam state in an attempt to tranquilize and treat it.

The attacks on the one-horned rhinoceroses have sparked outrage in the state, home to the world's largest concentration of the rhinos. The region is about 155 miles east of Gauhati, the state capital.

Poachers shot two rhinoceroses each on Wednesday and Thursday, two of them fatally, on the fringe of the Kaziranga National Park, taking advantage of heavy rains which have caused flooding across Assam state in recent days. The flooding has killed 18 people and forced 1.4 million to flee their homes.

The poachers escaped with the horns of the four rhinos, the state official said on condition of anonymity because he is not authorized to talk to the media.

Indian Environment and Forests Minister Jayanti Natarajan ordered an investigation by the federal Wildlife Crime Control Bureau to be completed within a week. "I am determined to ensure that these criminals are brought to justice," she said.

Much of the 185-square mile Kaziranga National Park also was flooded by the rains, drowning two rhinos and at least a dozen other animals, said Suresh Chand, Assam's chief wildlife warden.

Rhino horn powder is coveted in some Asian countries as a medicine or an aphrodisiac and its popularity has led to a rise in rhino poaching.

An estimated 2,500 out of the world's 3,000 one-horned rhinos live in Kaziranga.