The Copenhagen Zoo, which was in the news last month over killing of a young giraffe, is now making headlines again. This time, the zoo has killed four healthy lions, including two cubs.

The lions were killed to accommodate a new lion that arrived at The Copenhagen zoo March 25.

According to the zoo authorities, two adults and two ten-month-old cubs were killed to prevent competition between lions and maintain the "pride's natural structure and behavior," the Associated Press reported.

"Now that two young females born in 2012 have become mature and are healthy, they can take over from the old female and form a strong triangle with the new male," the zoo said in a statement.

"Due lion flock's natural structure and behavior Zoo had to kill the two old lions and two young lions who were not old enough to fend for themselves and also would have been killed by the new male lion as soon as he got the chance," the zoo added.

The lions' body parts will be used for research, according to Reuters.

The death of a giraffe named Marius at the zoo on Feb. 9 was criticized by the international media and the public. The giraffe was killed and fed to the lions (the ones that were killed recently) in the presence of children. The zoo had defended the killing of Marius saying that it was done to prevent inbreeding and to ensure a healthy population of giraffes.

The Copenhagen Zoo said that it isn't afraid of a similar outcry following the killing of lions.

"I think people are more enlightened after Marius," Steffen Stræde, the head of the zoo told Ritzau news bureau, according to The Copenhagen Post. "Marius hasn't made us the least bit afraid, because what we are doing is the most correct thing to do."