United Airlines temporarily halted transportation of animals on its flights after several animal-related incidents. Passengers can still bring pets on board in the cabin; the decision affects only pets stowed in cargo holds.

The airline is conducting full investigations of the incidents and has not released information on when the program might return. The full review should be finished by May. United released an official statement about the decision.

“We are deeply committed to the safety and comfort of the animals and pets in our care. We are conducting a thorough and systematic review of our program for pets that travel in the cargo compartment to make improvements that will ensure the best possible experience for our customers and their pets. To achieve this outcome, we will partner with independent experts in pet safety, comfort and travel.

While we are doing this review, effective immediately we will not accept any new reservations for PetSafe, our program for pets that travel in the cargo compartment. We expect to complete our review by May 1, 2018.

We will honor any existing PetSafe reservations confirmed as of March 20, 2018, although we will assist any customer that wishes to cancel their reservation. In the meantime, we are proactively reaching out to customers with confirmed reservations between today and May 1 to inform them of this announcement and explain what this means for their travel.

This suspension does not affect pets that travel with us in the aircraft’s cabin. We are also reviewing this service and have already announced that beginning in April we will issue bright colored bag tags to help better identify pets who are traveling in-cabin.”