36-year-old Tyree Eric Mansell has ties to Philadelphia, Lansdowne, and Yeadon.
Police say he is considered armed and dangerous.
Anyone with information should contact Marple Township Detectives at 610-356-1504.
Two brothers and a juvenile were previously charged in connection to the crime.
Action News has learned the juvenile is now being charged as an adult, therefore we are now naming him in this story.
17-year-old Abudllah Hartage of Philadelphia was formally arraigned Wednesday.
Only Action News was there as police led him away in handcuffs.
Jamain and Sterling Wallace were arraigned Tuesday on robbery and assault charges.
Police say the four broke into a house on Old Cedar Grove Road in Broomall on Monday afternoon.
"It is brazen. We have a very safe community. Our crime rate is low. It's a relatively safe area so this upsets people," Marple Township Police Chief Tom Murray said.
It was in the middle of the day around 1:00 p.m. when there was a knock at the door. A teenager opened the door.
"The 17-year-old answered the door, they forced their way in, smacked him in the head with a weapon. He screams. Mom is alerted and she comes running," Murray said.
The teen was struck with a pistol.
Police say the intruders ordered the teen and his mom upstairs at gunpoint and then ransacked the room until they found a safe full of money and jewelry.
"They force mom to open the safe, they take proceeds from safe which was a large sum of money," Murray said.
The men then tied the mom and her son up using an extension cord and clothing before taking off.
It turns out one of the victims got a good description of the getaway car and was able to call police.
Minutes later, an officer spotted the vehicle nearby and performed a traffic stop.
The suspects fled on foot and police gave chase. One of the men tried to hide under a deck.
In the end, police arrested the Wallace brothers, along with a juvenile.
The Wallaces are each being held on $500,000 bail.
Investigators say the victims are an Asian family who own a bar that produces a lot of money, and they believe the family was targeted.