MIAMI -

Police in Miami continue to look for a robber who knocked out an 18-year-old woman when he stole her cell phone.

The robbery happened in front of Miami Dade College's Wolfson campus in downtown Miami about 6:30 p.m. Saturday.

The woman, Janet, was walking to her car after finishing work.

"Someone told me to look back, so I looked back, and then I saw the two boys and they were just looking at me kind of strange, so I got scared, and then I adjusted my purse and I pulled my phone out and I pretended to talk to somebody," she said.

Janet suffered scrapes to her face and hands, a broken tooth and swollen lip.

"I'm crying and I look at my hands and I have blood everywhere and I think that's right when I blacked out again," she said.

An undercover police officer found her and had her taken to Jackson Memorial Hospital's Ryder Trauma Center, where she woke up.

"I have no idea who he is but I want to thank him," she said.

Police arrested 16-year-old Lonnie Welds in connection with the robbery. According to an arrest affidavit, Welds is being charged with strong arm robbery, conspiracy to commit strong arm robbery, resisting without violence and aggravated battery.

Anyone with information on the robbery is asked to call Miami-Dade Crime Stoppers at 305-471-TIPS.