YOUNGSTOWN, Ohio - Police have a warning for people trying to buy or sell phones and other valuables through online apps and services like Letgo, Craigslist, Facebook and Buy/Sell/Trade.

The Youngstown Police Department says detectives are investigating several robberies linked to the Letgo buy/sell app.

In several instances, people have been robbed after meeting with alleged buyers they had contacted through the Letgo and similar apps.

Most of the robberies are being done by juveniles or young adults.

They respond to the ads posing as older people to make the buyer or seller feel more comfortable.

For example, police say a male wants to buy a phone and says he works at a local business. He asks the victim to meet at that business. Once there the victim is approached by a teenage male who claims that he is there to buy or sell the item.

Police say this should be a red flag and you should leave the area.

All of the robberies have been committed by people on foot.

Police have the following recommendations on how to stay safe while buying or selling items on these apps:

When setting the meeting get as much information on the buyer or seller as you can. This way you have an idea of who you are meeting with.

If they say they are a male, ages of 30 or 40 and a male teenager approaches you, there is more than likely an issue and you should leave the area, and not engage in the transaction.

Use common sense. 

Always conduct business during daylight hours. Avoid making transactions during dusk or nighttime.

Always do business in well lit, public places.

Never go to a vacant business or building, even if it is in a public area.

Never go to the home of a person who is buying or selling. Tell them you will meet in a public area. Make this mandatory in the agreement to buy or sell.

Never go to an area of the city where you are not comfortable. Police say areas to conduct business would be in the downtown business district like the Covelli Center. These areas are more than likely on camera and are high traffic areas. This is also an area with a higher police presence. Be visible from the roadway, and never go behind a business or building.

Be aware of your surroundings at all times. Know where you are. Know where you can go if you need help. Know your direction of travel (how you got there, and how you will get home). Know the exact address of the location that you have picked to buy or sell. Use your phone or GPS to get the location’s address and become aware of the area before you go to the set location.

When setting the meeting get as much information on the buyer or seller as you can. This way you have an idea of who you are meeting with. Example: if they say they are a male, ages of 30 or 40 and a male teenager approaches you, there is more than likely an issue and you should leave the area, and not engage in the transaction.

“Trust your gut!” If anything about the situation makes you feel uncomfortable, back out. Do not go to the location, or leave if you think something is wrong. If you are selling or buying a high dollar item, take someone with you. You are less likely to become a victim if someone is with you (this is good practice for any situation). Make sure you see the money, or an item before the transaction begins. Remember, you, more than likely, do not know the other person and they do not know you.

Also, if you are selling an item like a cell phone for $400, and a young teenager approaches you without a parent or guardian present, there is more than likely going to be an issue. Most young teenagers do not have that kind of money, nor would their parent or guardian let them make that type of purchase without them being present.

Make sure to always have your cell phone at the ready to call 9-1-1 in case an issue arises.