Federal agents concluded the three-day investigation of an attempted bombing suspect at two homes in Houston’s Southampton neighborhood Tuesday evening.

Agents were seen carrying several boxes and computer hard drives from the residences at 2025 and 2021 Albans.

Andrew Schneck, 25, was arrested Saturday after he was allegedly caught trying to wire a bomb at the base of the Dick Dowling monument near Hermann Park.

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Schneck pleaded no contest to illegally harboring chemicals in 2014. He was given probation and required to pay a nearly $160,000 fine.

Schneck returned to school and graduated from Austin College in north Texas, majoring in chemistry, a university official confirmed.

An attorney for Schneck petitioned the court for an early release from his probation. The petition was granted and Schneck was no longer prohibited from accessing chemicals or researching the manufacturing of explosives, as the probation rules stipulated.

Prosecutors say they found explosives at the Albans homes and set off a series of planned detonations Monday evening.

Neighbors expressed dismay that their homes and lives were threatened.

"The exact same thing happened four years ago, with the exact same man, who winds up with five years probation, and he’s out in two?,” said Southampton resident Bill Sloan.

Neighbors say they were told by investigators more chemicals were found by federal agents than they had expected, causing for a longer-than-anticipated search.

Schneck is expected to appear in court on Wednesday.