BERLIN (Reuters) - Migrants face executions, torture and other systematic rights abuses in camps in Libya, according to a report prepared for the German government by the German embassy in Niger, the Welt am Sonntag newspaper reported on Sunday.

“Authentic cellphone photos and videos substantiate concentration-camp-like conditions in so-called private prisons” operated by people smugglers, the embassy said in a diplomatic cable sent to the chancellery and other ministries, according to the newspaper report.

“Executions of countless migrants, torture, rapes, bribery and banishment to the desert are daily events,” it cited the embassy’s report as saying.

“Eyewitnesses spoke of exactly five executions a week in one prison - with advance notice and always on Fridays - to make room for new migrants, i.e. to increase the human throughput and revenues of the smugglers,” it continued.

News of the embassy report comes ahead of a meeting of European Union leaders in Malta next week to discuss ways to control migration from Africa.

German Chancellor Angela Merkel also raised concerns about conditions in Libya in a webcast on Saturday, saying Europe should work with the North African country to control illegal migration, but could not sign a deal similar to that reached with Turkey last year until it became more stable.

Ska Keller, who heads the fraction of the pro-environment Greens in the European Parliament, said the German government should work to prevent any kind of an agreement with the Libyan government if it was aware of human rights abuses.

Signing a migration deal with Libya meant that people would be “sent back into a catastrophic and inhumane situation,” the newspaper quoted her as saying.

Interior Minister Thomas de Maiziere told the newspaper that U.N. conventions provided refugees rights to sanctuary, but did not guarantee them the right to choose where they would go.

De Maiziere and other EU interior ministers are moving to finance camps in Africa where the U.N. refugee agency and aid groups would process migrants to prevent them from trying to cross the Mediterranean to Europe.

Libya sank into chaos following the 2011 overthrow of veteran ruler Muammar Gaddafi, and the new U.N.-backed government in Tripoli exercises no control over its territory.

The sea crossing from Libya to Italy, operated by people-smugglers based in the North African country, is now the main route for migrants bound for Europe.

A record 181,000 mainly African boat migrants reached Italy last year, taking the total number of arrivals in the past three years to more than half a million.