Transit officials announced today the creation of memorial funds to benefit the families of two transportation workers gunned down by a colleague at a downtown bus terminal this week.

Benjamin Mwangi, 37, and Michael Stevenson, 55, were killed Tuesday by 47-year-old Lonnie Glasco of El Cajon, who in turn was fatally shot by police at the downtown Metropolitan Transit System complex where the three worked.

"We are doing all that we can to help the families involved in this tragic incident," MTS Chief Executive Officer Paul Jablonski said.

Authorities have disclosed no motive for Glasco's rampage, which began shortly after he ended a shift at the bus yard on 16th Street, near Petco Park.

The 29-year MTS employee walked into a staff lounge shortly after 2 a.m. Tuesday and said, "Nobody's going to leave," according to San Diego police.

After speaking briefly with several people inside the break room, Glasco walked out and shot Stevenson and Mwangi, the former in an office and the latter in a parking area, SDPD Lt. Kevin Rooney said.

Mwangi, a Lemon Grove resident who had worked for the transit agency since 2007, died at the scene. Stevenson, a 31-year MTS employee who lived in City Heights, was pronounced dead at UCSD Medical Center about 12 hours later.

Officers responding to reports of the shootings found Glasco standing near a bus service bay, still armed. Refusing orders to drop his gun, Glasco called his family on his cell phone, then pointed his gun at police, Rooney said.

SDPD Officers Kelly Besker, Kelly Copeland and Jared Wilson opened fire, killing him.

Glasco's relatives have declined to speak to reporters but sent a message offering their "deepest condolences to all those affected by this tragedy."

We do not know why this tragedy occurred ... and we are all truly sorry," the statement read.

Mwangi, who was employed by the MTS as a maintenance foreman, is survived by his wife, Mary, and two children, ages 10 and 17. Stevenson, a diesel mechanic, leaves behind his wife, Jeri.

Checks payable to the Ben N. Mwangi Memorial Fund and the Michael B. Stevenson Memorial Fund may be sent to the Metropolitan Transit System, care of Memorial Funds, 1255 Imperial Ave., Suite 1000, San Diego, CA 92101.