Local tradition suggests that on the morning of April 21, 1775, A British naval cutter anchored at the mouth of the Ipswich River. In response, the local alarm list mobilized but did not engage the enemy. No fighting ever broke out between the ship's crew and the militiaman. Nevertheless, an unfounded rumor began to spread inside the town that British regulars had landed and were laying waste to everything before them. With most Essex County minute and militia men away at the Siege of Boston, a massive panic set in. The rumor quickly spread to other towns.
A few hours later, it reached as far away as Newburyport. A minister named Carey was holding a meeting when alarm rider Ebenezer Todd interrupted the meeting and announced "“Turn out, turn out, for God’s sake,” he cried, “or you will be all killed! The regulars are marching on us; they are at Ipswich now, cutting and slashing all before them!”
The fright continued west to Haverhill and Andover. An early 19th century account of the incident suggests an alarm rider instructed Haverhill residents to "Turn out! Get a musket! Turn out . . . the regulars are landing on Plum Island!"
As panic set in, many residents began to gather their valuables and fled as far north as Exeter and Portsmouth, New Hampshire. Many Essex County residents overwhelmed ferries as they tried to cross the Merrimack River. Period accounts suggest Amesbury, Salisbury and Rowley were completely abandoned by its residents.
The residents were so overcome with fear and despair that they began to turn on each other in order to secure their escape. According to one period account "a Mr. ___, having placed his family on board of a boat, to go to Ram island, for safety, was so annoyed with the crying of one of his children, that he exclaimed, in a great fright, 'do throw that squalling brat overboard, or we shall all be discovered!'"
Some residents refused to flee. One Newbury account suggests an elderly resident took up a defensive post at his front door, loaded his musket and declared he intended to “shoot the devils" when they arrived.
The panic continued well into the early morning of April 22, 1775. By then, residents of Exeter had begun to suspect the entire ordeal was an unfounded rumor. In turn, the town dispatched an alarm rider towards Newburyport with a message that the account of a British army invading Essex County were false.
Shortly thereafter, many residents returned to their homes.