ALMATY (Reuters) - The sister of the Uzbek immigrant accused of killing eight people in New York said her brother might have been brainwashed and appealed to U.S. President Donald Trump on Friday to ensure he gets a fair trial.

Sayfullo Saipov, the suspect in the New York City truck attack, is seen in this courtroom sketch appearing in Manhattan federal courtroom in a wheelchair in New York, NY, U.S., November 1, 2017. REUTERS/Jane Rosenberg

Sayfullo Saipov, 29, was charged in a federal court on Wednesday with driving a rented pickup truck down a riverside bike trail, crushing pedestrians and cyclists, in support of Islamic State.

A dozen more people were injured in the city’s bloodiest single attack since Sept. 11, 2001. Trump called for Saipov to receive the death penalty.

Speaking from Tashkent, the capital of Uzbekistan, Saipov’s sister, Umida Saipova, said she hoped Trump would help ensure her brother was given “more time” and “a fair trial”.

She told Reuters by telephone that she and her family had been shocked to see Saipov grow a long beard after he got married in 2013.

Umida Saipova told Radio Free Europe (RFE) that her family believed that her brother may have been brainwashed.

“We don’t know who has brainwashed him,” Saipova said. “Perhaps he’s become part of some organized group. I don’t know, honestly, how long it will take for his head to get rid of that poison, but I’m sure he will come to his senses, God willing.”

She said she had spoken to her brother the day before the attack.

“He was in a good mood. It was a usual, good conversation,” she told RFE.

Saipov’s mother, Mukaddas, told Reuters she last saw her son in August when she visited the United States. The attack was a “total shock” to the family, she said.

“I was shocked by the news and I have been in hospital (since then) until this afternoon,” she said.

Mukaddas said Sayfullo told her in August he missed Tashkent. She wanted to bring him home, but could not do that because his youngest child was only 20 days old, she said.

Sayfullo never complained about his life in the United States and was able to support his family and help his parents at the same time, she said.

“He was kind with all of his friends,” Mukaddas said.

“No, he was not religious and never visited mosques because he was always busy with studying and then working.”

Trump has tweeted of Saipov: “should move fast. DEATH PENALTY!”

Umida Saipova told RFE she and her family hoped her brother would not be sentenced to death in some rushed show trial. Amid unconfirmed reports that the Uzbek authorities are questioning her family, she added that she did not know where her father and uncle were.