LONDON, Ont. -- The sudden disappearance of several components on a historic downtown building has stumped local heritage advocates, and now downtown London's largest landlord is facing questions from city hall.

The Architectural Conservancy of Ontario's (ACO) London branch is surveying recent changes to the front of the Wright Lithographing Building on Wellington Street just north of Dundas Street.

The president of ACO London, Jennifer Grainger, says two important features are missing.

“The clock and the lettering are to be conserved and we don't even know where those are at the moment.”

Built in 1902, the building was once home to London Life (now Canada Life).

Grainger says it is showing the effects of being vacant for many years.

“It's looking really rough, and when you see it looking that way on the outside you also wonder what's happening to it on the inside?”

The Wright Lithographing Building is currently owned by downtown's largest landlord Farhi Holdings Corporation.

Founder Shmuel Farhi tells CTV News the sign and clock are safe, “We're doing our very best to restore the sign and the clock and we will do our best to put it back.”

In a statement city hall says it's now aware of the situation.

"The city has met with a representative of the property owner, and clarified their obligations under the Ontario Heritage Act. The city is working with the representative to obtain the necessary information for a Heritage Alteration Permit"

Farhi says this when asked why he did not first obtain a Heritage Alteration Permit before exterior changes began, “Listen, I'm not the one who took the clock down, the majority of the clock was done by vandalism. Did they take care of heritage restoration?”

City hall will soon ensure the building is safe from the elements, "The city has also received a property standards complaint. The city will inspect the subject building for compliance including bylaw requirements for securing and heating vacant heritage designated properties."

Grainger says the processes are intended to help landlords protect their heritage buildings.

“You might actually be damaging the building and it might end up having some serious structural problems down the road.”