PRAIA DA LUZ, Portugal (Reuters) - Portuguese police have insufficient evidence to arrest anyone in the hunt to find the kidnapper of four-year-old Madeleine McCann but are focusing on the resort where she disappeared, police said on Thursday.

Madeleine disappeared from her bedroom at a hotel resort in the Algarve two weeks ago as her parents dined nearby.

Chief inspector Olegario Sousa said police continued to follow their strongest lead in the investigation, which has centred on foreigners in the small Praia da Luz resort.

"The greatest concentration (of investigators) is in the Algarve and more concretely, in the zone," Sousa told reporters. "At this moment we don't have enough evidence to arrest anyone."

Sousa said police had interviewed and searched the house of a computer technician in the resort, who has been identified by local media as a Russian man. Police took computers from the house and they "are now being examined", Sousa said.

The technician was questioned as a witness in the case but Sousa said a "witness can become a suspect."

So far one suspect has been identified by police -- a 33-year-old who lives in the area -- but his name has not been made public.

Police searched a villa on Monday close to the resort complex from where Madeleine went missing more than a week ago and took a British man, Robert Murat, away for questioning.

A close relative of the girl's parents, Kate and Gerry McCann, said on Thursday the parents had been overwhelmed with offers to help find their daughter.

"They have been totally overwhelmed by offers from individuals, small companies and large multinational corporations," close relative Michael Wright said in a televised statement. "Their purpose is to turn hope into action."

The McCanns launched a campaign on Wednesday, hoping to raise awareness and bring their daughter back.

Wright said the www.findmadeleine.com Web site had received five million hits on Thursday, a day after it was set up.

Soccer stars including David Beckham and Portugal's Cristiano Ronaldo have made appeals for Madeleine while wealthy individuals, including author JK Rowling, have offered large rewards for information leading to her return.