Sketch of sexual assailant

Police have issued a composite sketch of a sex offender who, cops say, entered a dentist's office on Castor Avenue near Pratt Street, Frankford, yesterday and attempted to sexually assault a 35-year-old woman staff member.

The man is described as black, about 6 feet, 30 to 35 years of age, wearing a dark-colored baseball cap, a dark hooded sweatshirt and an old-style green and silver Eagles jacket. Anyone with information about his identity should call the Special Victims Unit at 215-685-3251 through -3254.

Slaying victim ID'd

A man who was shot dead in North Philadelphia earlier this week was identified yesterday as Kahil Martinez, 32. Martinez, of 5th Street near Diamond, was gunned down at 4th and Norris streets about 6 p.m. Wednesday. He died shortly after at Temple University Hospital. Homicide investigators said they know of no motives or suspects in the slaying. Tipsters can call 215-686- 3334 or -3335.

Teenager shot in North Phila.

A 16-year-old boy was critically wounded when he was shot four times in North Philadelphia last night. Police said the victim, whose name wasn't released, was hit in the hip, arm and abdomen on Myrtlewood Street near Cumberland about 7 p.m. He was admitted to Temple University Hospital in critical condition. Police had made no immediate arrests. Tipsters can call 215-686-3093.

Reward for prison escapee info

The U.S. Marshals Service is offering a $10,000 reward for information leading to the capture of Oscar Alvarado, a murder defendant, who escaped from the Curran-Fromhold Correctional Facility on Thanksgiving. Authorities are "very confident" that Alvarado was at 30th Street Station on Black Friday, as seen in a station store surveillance video. Tipsters can remain anonymous and call 877-258- 1094.

Bike lanes mean more cyclists

Rina Cutler, deputy mayor for transportation and utilities, said that after trying out bike lanes on Spruce and Pine streets in Center City for about two months, she will recommend to Mayor Nutter that they become permanent. The Streets Department found that the lanes, from 22nd Street to Front on Pine, and from 2nd Street to 22nd on Spruce, have boosted bicycle ridership, with cycling up 65 percent on those streets during peak traffic hours.

Man charged in child-porn case

A Marcus Hook man has been charged with 50 counts of possessing and disseminating child porn, District Attorney G. Michael Green announced yesterday.

Police tracked down David Walton, 35, through a file-sharing network and found the illegal photos and movies on his computer, including one depicting a 3-year-old child. He admitted to possessing the child porn, according to the arrest report.

- Staff and wire reports