GUATEMALA CITY (AP) — Guatemalan families awaiting word on the fate of relatives involved in a deadly migrant smuggling accident in southern Mexico are now also living with the terror of extortionists telling them their loved ones have been kidnapped.

In the vacuum of official information following Thursday's deadly crash that left 55 migrants dead, opportunists are demanding money from their families for information.

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In its desperation, one Guatemalan family had published its phone number on social media hoping for information about their missing relative. On Monday, they shared with an AP reporter a screen capture showing a Mexican phone number demanding $3,000 if they wanted to see him again.

The caller even sent what appeared to be an altered photo that superimposed the relative's face on the body of another migrant.

The extortion is especially cruel because the families are distraught, poor and in most cases in debt for thousands of dollars for the failed smuggling attempt.

"We're scared," said the brother of one migrant, who though living in the United States requested anonymity out of fear. "It says there are 40 kidnapped. We don't know if my brother could be there."

On Thursday afternoon, a semi-trailer packed with migrants flipped in the southern Mexico state of Chiapas. It was believed to have been speeding, lost control on a curve and smashed into a steel pedestrian bridge, spilling bodies across the road.

Authorities have struggled to make identifications and in that lack of official information, criminals have entered looking for profit.

The Guatemalan government made phone lines available for families of few resources, many of whom do not speak Spanish, but families say they've been told nothing official.

Guatemala sent a high-level delegation including Foreign Minister Pedro Brolo to Mexico on Friday. They met with the injured in Chiapas and then went on to Mexico City to meet with Mexico Foreign Affairs Secretary Marcelo Ebrard.

Guatemala's government announced three days of mourning for victims Monday.

Thousands of Guatemalans continue to migrate north, hoping to reach the United States. Experts estimate 300 to 500 leave daily and pay smuggling on average $10,000. To come up with that money they often sell their belongings, hand over the deeds to their homes and take loans from relatives.

Those who successfully arrive in the U.S. provide a critical income source to Guatemala in the money they send home to their families. The more than $11 billion Guatemalans send home annually accounts for more than 14% of Guatemala's gross domestic product.

From January through November, nearly 15,000 Guatemalans were deported from the United States by air. During the same period, another 58,000 were deported from Mexico by land and air.