Vienna - Five young people who had been in serious condition after consuming poisoned drinks in a Vienna bar were on the road to recovery, Austrian broadcaster ORF reported Monday.

On Sunday evening, police arrested a male suspect for secretly putting an unknown substance into the drinks of the three men and two women earlier that day.

So far, the suspect's motive was unclear. However, it was still not certain if the five, aged between 20 and 30, had really not known about the substance they were taking in, ORF reported.

The drug LSD or a sedative might have been used, investigators were quoted as saying by Austrian media.

The party-goers had collapsed nearly immediately after consuming the tainted drinks and were brought to hospitals. (dpa)