The Toon Teenagers conceded in the opening stages of the cup clash at St. James' Park following Seb Ferdinand's close-range finish before the hosts responded in quick fashion as Lewis Miley's impressive strike levelled the tie.

Despite Amario Cozier-Dubbery's deflected effort on the stroke of half-time regaining the Gunners' one-goal cushion, Newcastle captain Ben Parkinson levelled shortly before the hour mark after converting from Johnny Emerson's cross.

However, Kamara broke Newcastle hearts in the dying stages as the Arsenal substitute steered the ball home inside the penalty area as the Gunners prevailed in a thrilling five-goal encounter.

Graeme Carrick's side booked their place in round four following a 3-2 away victory at Charlton Athletic, coming from behind to win at The Valley, and were aiming to secure an away trip to Watford in round five ahead of facing the North London outfit, managed by former Gunners midfielder Jack Wilshere.

In front of 983 spectators, Arsenal created the opening goalscoring opportunities as the lively Cozier-Duberry flashed a low effort wide of the left-hand post before crashing an effort off the side netting minutes later.  

Newcastle fell behind in the 15th minute as Ferdinand broke the deadlock from the Gunners, scrambling his effort into the right-hand corner after the United defence were unable to clear the ball to safety.

With the likes of Michael Carrick, Sean Longstaff and Paul Dummett in attendance, Newcastle's youngsters equalised through Miley's excellent strike as the 16-year-old, who made his Magpies first-team debut in a 5-0 win against Al Hilal in Riyadh last month, drove into the penalty area from the left flank before drilling a fierce effort beyond Arsenal goalkeeper Noah Cooper.

After Parkinson saw two low shots at goal smartly held by Gunners goalkeeper Noah Cooper, Arsenal restored their lead through Cozier-Duberry as the 17-year-old winger's strike towards goal took a wicked deflection, deceiving Newcastle goalkeeper Aidan Harris as the ball flew in the opposite direction of the teenage shot-stopper.

Newcastle, who claimed a 4-2 win against their Arsenal counterparts in the Premier League Cup earlier this season, equalised for a second time in the cup contest as Parkinson converted in front of the Gallowgate End, getting onto the end of Johnny Emerson's inviting cross before the Durham-born forward steered the ball beyond Cooper, recording his ninth goal at under-18 level this term in the process.

Harris produced a crucial save to prevent Arsenal regaining the lead for a third time after turning Ferdinand's effort out for a corner with an excellent fingertip save before the 16-year-old pushed away Jimi Gower's shot at his near post.

With the possibility of extra-time looming, Newcastle were dealt a sickening blow in the 87th minute as Kamara netted for the North London outfit, latching onto Ferdinand's pass from the right flank before steering the ball home to the disappointment of the United players.

Newcastle United Under-18s: Aidan Harris, Lucas Cooper (Thomas Bryant 90), Beau Beresford (Shaun Mavididi 54), Scott Bailey, Ciaran Thompson, Rory Powell, Darren Palmer, Dylan Charlton, Ben Parkinson, Lewis Miley, Johnny Emerson.

Subs not used: Carter Milmore, Adam Harrison, Luke Craggs, Logan Watts, Sean Neave.