ABOARD THE ASTRAL ON THE MEDITERRANEAN SEA – A Spanish rescue ship patrolling the Mediterranean Sea said Friday that Italian officials told it to let the Libyan coast guard respond to a distress call from a smuggling boat carrying 100 migrants, only to hear reports shortly afterward that 100 migrants were missing and feared dead in the same area.

The account by Proactiva Open Arms came as EU leaders in Brussels signed a deal aimed at controlling migration that steps up support for the Libyan coast guard and demands that humanitarian and other ships operating in the Mediterranean not obstruct their operations. The moves are part of efforts to stop smugglers from operating out of the lawless, North African country.

Open Arms founder Oscar Camps said such demands will cost the lives of people at sea.

"The problem is there won't be anyone to witness this and denounce it, that is what will happen starting now," Camps said.

In the latest incident, the Open Arms crew intercepted a radio transmission about 8 a.m. Friday between European military and Libyan coast guard giving details of a rubber boat in distress with 100 migrants onboard, said Open Arms head of mission Ricardo Canardo.

But an official distress signal was only received by boats in the region on the Navtext navigation system 90 minutes later.

When Open Arms called the Maritime Rescue Coordination Center in Rome to offer help, officials said the Libyan coastguard had the situation covered and that no assistance was needed.

Shortly later, they received the news that over 100 people were missing at sea in that same region.

"We suspect it is the same people," Canardo said.

The Libyan coast guard said they rescued 16 migrants, but that the boat capsized east of Tripoli with or about 100 on board who are missing at sea and feared dead. A survivor spoke of 125 people on board, including women and children, on board.

Riccardo Gatti, captain of another Proactiva ship, the Astral, said he has witness tragic rescues performed by the Libyan coast guard who lack the most basic equipment, including life vests.

In the past, the Libyan coast guard has shot in the air during a rescue operation involving Open Arms ships, and aid workers say they have never responded to Open Arms' requests to help in a rescue.

"For months now, (the Libyan coast guard) has been presented as an official body, formal, very well-trained and legal, and these are the same people who have shot at us, who have kidnapped us," Gatti said. "All of this is theater."

The Astral left Malta early Thursday with four European parliamentarians on board as observers to join Open Arms. However, the boat is unlikely to be able to return to Malta, as the EU island nation close to Libya has closed its ports to humanitarian ships as it investigates the actions of a private German rescue mission accused of allegedly violating maritime law.

The Open Arms has already been denied a request to make port in Malta to resupply, and a similar request to Italy has not been answered.