A homeopathic doctor was today hacked to death and a professor was seriously wounded by machete- wielding Islamic State militants in Bangladesh amid a series of brutal attacks on secular activists and minorities by Islamists.

Sanaur Rahman, 58, a homeopathic doctor, was riding home on his motorbike along with Saifuzzaman, assistant professor of Bangla literature at Islami University, while they were attacked by the assailants in Kushtia town this morning.

Rahman died on the spot while Saifuzzaman has been shifted to Dhaka Medical College Hospital in critical condition, police said.

The deceased along with Saifuzzaman was going to his native village at Shishirmath to give free treatment to local people, Sahabuddin Choudhury, officer-in-charge of Kushtia Model Police Station, said.

They were intercepted by three to four people and attacked with machetes indiscriminately, he said, adding the assailants attacked them in a similar fashion that bears the hallmark of previous murders of bloggers and secular activists.The Islamic State group claimed responsibility for the attack.

"Fighters from the Islamic State assassinated a doctor who called to Christianity in Kushtia, western Bangladesh," the IS-affiliated Amaq news agency said in a brief Arabic message, according to SITE Intelligence Group.

Proloy Chisim, superintendent of police (SP) of Kushtia, said that they were also probing whether personal enmity was behind the murder. Both the doctor and the professor were fans of a mystical musical tradition known as Baul, which is popular in western Bangladesh.

Rahman also used to arrange musical concerts based on Baul ideology at his native village every Friday, his relative said.

There have been systematic assaults in Bangladesh in recent weeks especially targeting minorities, secular bloggers, intellectuals and foreigners.

Earlier this month, a 65-year-old Muslim Sufi preacher was hacked to death by unidentified machete-wielding assailants in northwest Bangladesh, two weeks after a liberal university professor was killed in a similar attack claimed by the dreaded ISIS terror group.

The country's first gay magazine editor was brutally murdered along with a friend in his flat in Dhaka by Islamists two days after the professor's murder.

Less than two weeks ago, a Hindu tailor was hacked to death by machete-wielding ISIS militants in his shop in central Bangladesh.