Pakistan, April 30 -- New Zealand's Court of Appeal has rejected an attempt by Christchurch mosque attacker Brenton Tarrant to overturn his conviction and sentence for the 2019 mass shooting that killed 51 people.

Read More: New Zealand mosque attacker to face survivors, victims' families in

Tarrant, a white supremacist, had pleaded guilty to carrying out New Zealand's deadliest modern-day terror attack and was sentenced in August 2020 to life imprisonment without parole, the harshest sentence in the country's legal history.

In his appeal, filed earlier this year, the 35-year-old argued that alleged "torturous and inhumane" prison conditions during his detention affected his mental state and prevented him from making informed decisions...