A 23-month-old boy wandered down a grassy slope from a lakeside playground in Howard County yesterday and drowned in the shallow water, police said.

Alex Ferrera had been with a day-care provider at a group of swings and jungle gym equipment near Lake Elkhorn in Columbia yesterday morning. The day-care provider called police at 11:42 a.m. to report that he was missing, Howard police said.

An off-duty Secret Service agent who was nearby found the boy floating in the water not far from the shore, pulled him out and, with the help of a nurse, performed CPR on him, said police spokeswoman Jennifer Reidy. He was taken to Howard County General Hospital, where he was pronounced dead.

Reidy said police did not know how the child ended up in the lake. There are only a few dozen yards between the playground and the wooden boardwalk at the water's edge, and there is no fence or restraining structure to keep people from going into the lake. Some park visitors said yesterday that they frequently see children running from the playground to the water's edge to look at the swans and Canada geese.

"It appears to be, at this point, some sort of tragic accident," Reidy said.

To the parents pushing strollers along the boardwalk and hoisting kids onto swings at Lake Elkhorn Park yesterday, the child's death came as a chilling news on an otherwise tranquil, sunny day.

"That breaks my heart," said Phillip Liggins, 42, who was watching his 1- and 3-year-old sons toddle around the playground. "This really shouldn't happen, at least around here."

The 37-acre man-made lake was built in 1974 and is overseen by the Columbia Association. It is used by boaters and fishermen, and swimming is prohibited, said association president Maggie Brown. She said that once the cause of the child's death is determined, she would address such issues as lake safety.

"It's just really sad," she said. "My heart goes out to the parents."

Staff researcher Bobbye Pratt contributed to this report.