A 44-year-old Alexandria man indicted earlier this week on 27 counts of sex-related charges, including sodomy with male teen-agers and using young men as models in pornographic photographs, has been arrested by Alexandria police.

Lawrence E. Dickens, a free-lance photographer who lived in an apartment near Bishop Ireton High School in the Cameron Valley section, was arrested Wednesday. He was released on $5,000 bond. His arrest ended a four-month investigation that began after New York City police arrested Dickens on prostitution and obscenity charges last August. A 17-year-old Alexandria juvenile was with Dickens at the time of his arrest, according to court documents.

In this week's indictment in Alexandria Circuit Court, Dickens was charged with several counts of sodomy, prostitution of juvenile males, producing obscene materials involving juvenile males and contributing to the delinquency of minors. "Hundreds and hundreds" of pornographic pictures were found in Dickens' apartment, police said.

At least two of the five juveniles named in the indictment are Alexandria residents, according to court records. The majority of juveniles depicted in the photographs taken from Dickens' apartment and a trash dumpster outside it are runaways or hitchhikers from out of town, police estimated.

Dickens' apartment was put under surveillance and eventually searched after a citizen reported to police unusual activity at the apartment. Police removed photographic equipment, handcuffs, boxes of slides, 15 pornographic books and sexually explicit film and photographs. Also found was a typewritten memo for Dickens' "personal assistant" that listed "escort," photographic, darkroom and clerical duties to beperformed "at the rate of $2.50 anhour . . . "

The maximum sentence for any of the individual felonies listed in the indictment is 10 years. A trial date will be set Tuesday in Alexandria Circuit Court.