Question: The Oklahoma City bombing was a domestic terrorist truck bombing on the Alfred P. Murrah Federal Building in downtown Oklahoma City, Oklahoma, United States on which date, Terry Lynn Nichols, is an American who was convicted of being an accomplice in the Oklahoma City bombing?

Context paragraphs:
Alfred P. Murrah Federal Building: The Alfred P. Murrah Federal Building was a United States federal government complex located at 200 N.W. 5th Street in Downtown Oklahoma City, Oklahoma, United States.  It was the target of the Oklahoma City bombing on April 19, 1995 at 9:02am, which killed 168 people, 19 of whom were children under the age of six.  Half of the building collapsed seconds after the truck bomb detonated.  The remains were imploded a month after the attack, and the Oklahoma City National Memorial was built on the site.

Terry Nichols: Terry Lynn Nichols (born April 1, 1955) is an American who was convicted of being an accomplice in the Oklahoma City bombing.  Prior to his incarceration, he held a variety of short-term jobs, working as a farmer, grain elevator manager, real estate salesman and ranch hand.  He met his future conspirator, Timothy McVeigh, during a brief stint in the U.S. Army, which ended in 1989 when he requested a hardship discharge after less than one year of service.  In 1994 and 1995, he conspired with McVeigh in the planning and preparation of the Oklahoma City bombing – the truck bombing of the Alfred P. Murrah Federal Building in Oklahoma City, Oklahoma, on April 19, 1995.  The bombing claimed the lives of 168 people.

St. Joseph Old Cathedral (Oklahoma City): St. Joseph Old Cathedral is a parish church of the Roman Catholic Archdiocese of Oklahoma City located in downtown Oklahoma City, Oklahoma, United States.  It was the seat of the 'Diocese of Oklahoma City-Tulsa' from 1905-1931; and it was listed on the National Register of Historic Places in 1978.  The cathedral was severely damaged during the Oklahoma City bombing in 1995.

Oklahoma City bombing: The Oklahoma City bombing was a domestic terrorist truck bombing on the Alfred P. Murrah Federal Building in downtown Oklahoma City, Oklahoma, United States on April 19, 1995.  Perpetrated by Timothy McVeigh and Terry Nichols, the bombing killed 168 people, injured more than 680 others, and destroyed one-third of the building.  The blast destroyed or damaged 324 other buildings within a 16-block radius, shattered glass in 258 nearby buildings, and destroyed or burned 86 cars, causing an estimated $652 million worth of damage.  Extensive rescue efforts were undertaken by local, state, federal, and worldwide agencies in the wake of the bombing, and substantial donations were received from across the country.  The Federal Emergency Management Agency (FEMA) activated eleven of its Urban Search and Rescue Task Forces, consisting of 665 rescue workers who assisted in rescue and recovery operations.  The Oklahoma City bombing was the deadliest terrorist attack on American soil until the September 11 attacks six years later, and it still remains the deadliest incident of domestic terrorism in United States history.

Alfred P. Murrah: Alfred Paul Murrah (October 27, 1904October 30, 1975) was an American attorney and federal judge.  He was the namesake of the Alfred P. Murrah Federal Building, which was destroyed in the Oklahoma City bombing on April 19, 1995.

Oklahoma City bombing conspiracy theories: A variety of alternative theories have been proposed regarding the Oklahoma City bombing.  These theories reject all, or part of, the official government report.  Some of these theories focus on the possibility of additional, unindicted, co-conspirators or additional explosives planted inside the Murrah Federal building.  Other theories allege that government employees and officials, including US President Bill Clinton, knew of the impending bombing and intentionally failed to act on that knowledge.  Government investigations have been opened at various times to look into the theories.

Carol Ross Barney: Carol Ross Barney, FAIA (born 1949) is a Chicago architect, principal designer at Ross Barney Architects.  She became the first woman to design a federal building when commissioned as architect for the Oklahoma City Federal Building, which replaced the bombed Alfred P. Murrah Federal Building.  Ross Barney's other projects include the JRC Synagogue (LEED Platinum), James I Swenson Civil Engineering Building (LEED Gold) and the CTA Morgan Street Station.

Oklahoma City National Memorial: The Oklahoma City National Memorial is a memorial in the United States that honors the victims, survivors, rescuers, and all who were affected by the Oklahoma City bombing on April 19, 1995.  The memorial is located in downtown Oklahoma City on the former site of the Alfred P. Murrah Federal Building, which was destroyed in the 1995 bombing.  This building was located on NW 5th Street between N. Robinson Avenue and N. Harvey Avenue.

The Third Terrorist: The Third Terrorist: The Middle East Connection to the Oklahoma City Bombing is a book by journalist Jayna Davis about evidence of an alleged conspiracy behind the 1995 Oklahoma City bombing.  The Justice Department initially sought, but then abandoned its search for, a Middle East suspect.  The book was published in April 2004 by Nelson Current Publishers, and became a New York Times best-seller.  In contrast to conspiracy theories that the bombing was a false flag attack perpetrated by elements of the US government, the book presents a theory that links the Oklahoma City bombers to agents of Iraq and Al-Qaeda, operating under Iranian state sponsorship.

Timothy McVeigh: Timothy James McVeigh (April 23, 1968 – June 11, 2001) was an American domestic terrorist convicted and executed for the detonation of an ammonium nitrate fertilizer and nitromethane truck bomb in front of the Alfred P. Murrah Federal Building in Oklahoma City on April 19, 1995.  Commonly referred to as the Oklahoma City bombing, the attack killed 168 people and injured over 600.  According to the United States government, it was the deadliest act of terrorism within the United States prior to the September 11 attacks, and remains the most significant act of domestic terrorism in United States history.

Supporting paragraphs: Oklahoma City bombing Terry Nichols
Answer: April 19, 1995