Search For Natalee Holloway Continues

The search for Natalee Holloway the Alabama teen who disappeared during a high school graduation trip to the Dutch Caribbean island of Aruba, is continuing, nearly a year after her disappearance.

A team of several boats from Aruba's coast guard was planning to use sonar equipment Friday and focusing on the area off the shore of the hotel where Holloway stayed, at the northern end of the island, reports CBS News correspondent Bianca Solorzano.

Authorities have arrested seven people in connection with Holloway's disappearance and then released them for lack of evidence. On Saturday, they arrested Geoffrey van Cromvoirt, 19, saying he was suspected of "criminal offenses that may be related to the disappearance" of Holloway, who was 18 when she vanished. Officials have not provided details about why van Cromvoirt was arrested.

His beach friends still find his arrest hard to believe.

"I thought it was a joke. Geoffrey? I mean ..." Danielle Buffalini told Solorzano.

His defense attorney has released a statement, claiming the teenager was not working as a beach patrol member in May or June of last year.

The defense also stresses that van Cromvoirt is not friends with the three men arrested earlier in the case, Joran van der Sloot, Deepak Kalpoe and his brother Satish.

John Q. Kelly, an attorney for the Holloway family, said he was told by an FBI agent that van Cromvoirt's name had come up earlier in the investigation. Kelly said he had no other information about the suspect.

Aruba's chief prosecutor has told Kelly "they have sufficient evidence to hold him ... and they're continuing to interrogate him," Kelly said in a telephone interview from his New York office Thursday.

CBS News has obtained transcripts of secretly recorded conversations that van der Sloot and the Kalpoes had with one another. Just weeks after Holloway disappeared, the three were taped in the back of a police car accusing each other of lying and doing something to the Alabama teen.

In the transcripts, van der Sloot says to the Kalpoe brothers, "I know very well that you are afraid, that is, if you did something bad with the girl, and if they find the girl then we will see."

Satish Kalpoe answers "I'm not afraid, why must I be afraid?"

Deepak says "I want them to find the girl."

A judge on Tuesday approved a prosecution request to hold van Cromvoirt pending further investigation. He also was detained on suspicion of drug offenses.

Footage aired on an American television network showed a handcuffed van Cromvoirt, wearing a black hooded sweat shirt and blue jeans, coming out of a police station on Thursday evening. When he saw the television camera, he pulled his sweat shirt over his face.

A number of searches involving Dutch marines, the FBI and hundreds of volunteers have been conducted throughout the island and off the coast. More recent searches have focused on dunes along the island's north shore.