England bowler Stuart Broad has been charged by match referee Ranjan Madugalle with "throwing the ball inappropriately" during the second Test with Pakistan.
Broad threw a dead ball back at batsman Zulqarnain Haider, who would frustrate England with a knock of 88, during the third day at Edgbaston.
The 24-year-old seamer was charged with a level two offence for the incident.
The transgression can result in a one-Test ban, but a fine relating to a percentage of his match fee is likely to apply to Broad as he has not been punished for a similar incident before.
Graeme Swann, who claimed Test best figures of 6-60 on the third day, was quick to play down the flashpoint.
"Knowing Broady as I do, he certainly didn't have any malice behind it and he can't throw the ball hard enough to hurt anyone anyway," he said.
"He apologised straight away. It was just a sign of the frustrations that were going on."
Pakistan skipper Salman Butt, however, criticised Broad's actions.
He said: "Cricket is a gentleman's game but I think they got frustrated. The throw was just one thing. There were plenty of words as well, that everyone could see, and people kicking the bowling marks.
"It's just frustration when you have been bowling too long. It's not good to see people throwing balls intentionally at others and not even apologising properly."