Tunisia’s Radio Mosaique reported that Amri’s father said he had lost contact with his son, but that the suspect had been in touch with his siblings, according to Reuters.
The assailant, who is believed to be Afghan, injures five people, four of them tourists from Hong Kong.
According to German and Italia media reports, Amri left Tunisia sometime in 2011 after the Arab Spring uprisings, a wave of demonstrations and protests that took place across the Middle East.
Amri’s siblings have denounced the attack.
The interior minister of Germany’s most-populous North Rhine-Westphalia (NRW) state, Ralf Jaeger, said counter-terrorism officials had exchanged information about Amri, most recently in November, and a probe had been launched suspecting he was preparing “a serious act of violence against the state”.
Berlin police chief Klaus Kandt said Tuesday it wasn’t clear whether the man detained was really the driver. Broadcaster rbb said the suspect lost both his wallet and mobile phone while fleeing.
It also emerged Thursday that he might have been treated at a hospital before making his getaway, Britain’s Telegraph reported.
His asylum request was denied but, because he couldn’t be expelled, he was issued a stay of deportation paper – the document that police this week found in the mangled truck cabin.
A suspect believed to be the driver was picked up around 1 1/2 miles away, near the Victory Column monument.
“I know that it will be especially hard for us all to bear if it is confirmed that somebody carried this out who was given protection and asylum in Germany”, Merkel said.
Tunisian anti-terror police interrogated Amri’s relatives Wednesday in the central Tunisian town of Oueslatia, a spokesman, Sofiane Selliti, said.
Though still just a suspect, the more that emerges about Amri’s past, the more precarious the situation for German chancellor Angela Merkel and her government, under pressure from far-right groups for its liberal asylum policies that saw 890,000 people come into the country previous year, including Anis Amri.
The arrival of 890,000 refugees past year has polarised Germany, with critics calling the influx a serious security threat.
In a nationally televised statement in Berlin, Merkel said that people across Germany were mourning after the “horrific and unimaginable” deaths and injuries sustained in the capital on Monday evening.
Residents living near Boban S’ former home told Ruhr Nachrichten they recognised Amri, last seeing him around 10 months ago.
Abdelkader also urged his brother to surrender. He’s my cousin, I’ve known him since I was a kid.