EL PASO, Texas - A female tiger, caught in a feline love triangle, has killed her mate at a West Texas zoo, authorities said on Friday, in a rare attack that came after months of simmering jealousy.

Three-year-old Malayan tiger Seri killed 6-year-old Wzui at about 4 pm on Thursday in an enclosure at El Paso Zoo, zoo spokeswoman Karla Martinez said on Friday,

As soon as the incident was reported, zookeepers closed the tiger exhibit and veterinary staff were called. They examined Wzui, and found he was dead.

"Tragic incidents such as this are not unheard of but we don't consider this common," zoo Director Steve Marshall said. Marshall described the deceased tiger as very down to earth and loving and said he would "be greatly missed".

Malayan tigers are a critically endangered species, with just 500 or so of the animals remaining in the wilds of Thailand and Malaysia, according to the World Wide Fund For Nature.

Both Seri and Wzui were on loan from other zoos as part of the American Zoo Association's Species Survival Plan to aid in their conservation through captive breeding.

Marshall said keepers had not observed any signs of aggression leading up to the attack, and that the two cats had been seen playing affectionately at the exhibit earlier in the day.

However, in June, zoo authorities reported what they called a "tiger love triangle"  between Seri, Wzui and a 15-year-old female called Meli, who was transferred to El Paso from a zoo in Fresno, California, in 2001.

"The male tiger Wzui likes both females, but the two females don't like each other," the zoo said in a press release dated June 14. "The girls are jealous of each other," collections Supervisor Griselda Martinez said.

Staff expect that another tiger will be transferred to the El Paso Zoo to replace Wzui for breeding purposes.