The NFL is seeing an unusually high number of penalties early in the season, with 963 accepted flags through Week 4, according to ESPN data cited in a report Tuesday.

Week 4 alone produced 271 accepted penalties, the second-highest total for a single week in the 48-year tracking period. Twelve teams recorded at least 10 accepted penalties in their Week 4 games, while the Chargers and Seahawks combined for 30 penalties during Seattle’s 30-23 victory.

Offenses have accounted for much of the increase. Football analyst Warren Sharp found that offenses are being penalized at a rate of 6.18 flags per 100 snaps through the first four weeks, the highest rate for that portion of a season since at least 2000.

Sharp also found that offensive penalties on third and fourth downs in the second half have reached the highest level in his available data. Offensive penalties in the red zone have also reached a record level in the same data set, while defensive penalties are slightly lower than a year ago.

The surge has fueled criticism from fans and analysts who argue that frequent flags are disrupting the flow of games and wiping out significant offensive plays. The data, however, does not by itself establish whether the increase is the result of a league-wide officiating directive, changes in how teams are playing, or other factors.

The early-season numbers nevertheless represent a significant departure from recent years. With the regular season still in its opening month, the NFL will have to determine whether the elevated penalty rate is a temporary trend or something that continues throughout the season.