New Zealand mosque shooting suspect Brenton Tarrant visited Israel in 2016 for several days, Channel 13 news reports, as more details about the gunman emerge.

A senior immigration official tells the TV news station that Tarrant arrived in Israel from Turkey on October 25 using his Australian passport. He was granted a 90-day tourist visa, and left the country nine days later.

The official says Tarrant did not raise red flags during security checks.

Earlier on Sunday, police in Greece said Tarrant had visited the Greek islands of Crete and Santorini, and had traveled through the country twice, all in 2016.

Authorities in Bulgaria, Turkey, Croatia, and Hungary have also confirmed visits by Tarrant between 2016 and 2018, as he apparently studied battles between Christians and the Ottoman Empire.

In a statement, Greek police said Tarrant entered the country twice in 2016 on transit flights on November 29 and December 10.

In March 2016, he entered the country on a flight from Istanbul and stayed for a few days in Heraklion, Crete and Santorini.

Authorities are investigating any phone calls or purchases Tarrant made in Greece. On Tarrant’s rifle was written the Greek word meaning “Turk-eater” or, metaphorically, “Turk-slayer.”

The AP contributed to this report.