A man has been taken to hospital after he became unresponsive when he was arrested in Adelaide’s east on May 29.

South Australia Police said they witnessed an incident between a man and a woman on Payneham Rd in Royston Park at around 2:45am on Thursday.

During the arrest, the 42-year-old man from Modbury North condition declined and he “became unresponsive”, the department said, adding that no one was shot and no taser was used.

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Payneham Rd was closed between Lambert Rd and Lower Portrush was closed for a few hours. Credit: 7NEWS

The 42-year-old was taken to hospital, where he remains in an unknown condition.

Payneham Rd was closed between Lambert Rd and Lower Portrush Rd, but has since reopened.

Detectives are now investigating the incident.

More to come ...