The suspect in the deadly arson attack on a Kyoto Animation Co. studio in July who is in hospital with severe burns has recovered to the extent that he can practice speaking again, investigative sources said Wednesday.

Police have obtained an arrest warrant for Shinji Aoba, 41, on suspicion of murder and arson, among other charges, but have no prospect of arresting him yet as it is up to doctors to determine whether he can withstand confinement.

The company's studio in Kyoto's Fushimi Ward, the center of its anime production, was set ablaze on July 18 after Aoba is believed to have spread and ignited gasoline inside the three-story building, killing 35 people and injuring 34.

After Aoba was apprehended by local police near the scene, he was temporarily in a critical condition but has managed to recover to the extent where he could make simple gestures in early August.

According to the sources, Aoba has undergone skin graft surgery and is now in a stable condition. Though he is still being treated in an intensive care unit and needs a ventilator, he will be undergoing rehabilitation, including having speech therapy, the sources said.

As it is expected to take several more months before he is released from the hospital, the police are considering how best to proceed with their investigation, the sources said.

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Kyoto Animation, often referred to as "KyoAni" by fans, is known for works such as "K-On!" and "The Melancholy of Haruhi Suzumiya," which depict the everyday lives of high school girls.

Donations to the studio have exceeded 2.5 billion yen ($23 million), but it is likely to take a while for the company to recover, as about 20 percent of its employees lost their lives in the incident.

Among the 69 employees who died or were injured, some 75 percent were in their 20s and 30s, as the company is known to hire young animators as regular employees and conduct in-house training, while many other studios tend to rely on skilled freelancers.

Though some of the injured employees have returned to work, others have remained unable to do so for psychological reasons, the investigative sources said.

As a measure to help Kyoto Animation recover, the Kyoto prefectural government has set up a special bank account to accept donations.

Donations transferred to the bank account will be regarded as contributions to a local government and eligible for tax relief.

On Sept. 6, a film created by the anime studio was released for the first time since the arson attack, attracting many fans.

But the release of the series' next movie, originally scheduled for January, has been postponed, according to Kyoto Animation.