At a news conference at 18th Police District headquarters in West Philadelphia, Abraham called the task force "action-packed" and said she believed its effort to get illegal guns off the streets would "put a dent in the murder rate."
She also took the opportunity to again accuse Mayor Street of not doing enough to stem the city's surge in deadly violence, which has claimed more than 100 lives this year.
Street spokesman Joe Grace said Abraham's criticism was "unfortunate."
"We're fighting every day to reduce and prevent violence," Grace said, noting that the city would add 200 police officers this year and was pursuing major curfew and anti-truancy initiatives.
Last year, Philadelphia police confiscated 5,386 guns. The task force, which has hired former Philadelphia police detectives to act as special agents for the attorney general, has seized about 50 firearms.
One of those weapons was an AK-47 confiscated from Michael Westcott, 23, a convicted felon.
The assault rifle allegedly was purchased for him in December by Kenneth Goodman, 21, who then subsequently reported it stolen, authorities said.
Such reports are prompting more investigations by the task force and by Philadelphia police, who also have investigators dedicated solely to straw purchases and gun trafficking.
Natia Giles, 23, and Stephen Blackshear, 21, allegedly bought Westcott a .40-caliber Walther pistol. Giles then reported it stolen.
Giles and Blackshear face possible lengthy prison sentences if convicted.
Andre Trower, 28, made a straw purchase and then reported the gun stolen in June 2005, authorities said. However, Philadelphia police had already confiscated the handgun in March of that year.
Many straw purchases are committed by the girlfriends of convicts. Others have different motives.
Joanne Ricciardi-Clementi, 33, bought a Glock .40-caliber and a Smith & Wesson .40-caliber for her crack dealer in exchange for cash and drugs, authorities said.
Christine Leach, 34, and Jose Manuel Diaz, 34, made a straw purchase in exchange for $150, Abraham said.
Abraham also noted that "it's not uncommon for a parent to buy a gun for their kids."
Contact staff writer Robert Moran at 215-854-5983 or firstname.lastname@example.org.