A search for the parents of a 3-year-old wandering on the street in a diaper led to the discovery of a drug lab inside a home in Fullerton on May 19, authorities said.

Officers first responded to West Gage Avenue near South Woods Avenue after a caller reported that a toddler is seen on the street alone, according to Fullerton Police Department’s Capt. Jon Radus.

When officers were looking for the parents, they found a drug lab inside a home near the 700 block of West Gage Avenue, Radus said.

Daniel Ortega, 60, Frank Ortega, 82, Nicholas Ortega, 32, and Samantha Michael, 30—all Fullerton residents—were arrested as a result, according to Radus. A search warrant was issued, and hazardous materials were found inside the residence.

Nearby houses were also evacuated as experts from the police department assessed the situation, he said. The area was later cleared after the hazardous materials were removed.

The child was placed in protective custody while the search for the parents continues.

No further information about the case was available.