which department are you working in vs In which department you are working

Some examples from the web:

• I welcome the fact that Commissioner Patten and his department are working in this area.
• At which department are you actually working?
• Ambassador Underwood and the State Department are working with all interested parties toward that end.
• As the first point of this programme, my departments are working on an improvement of the Community system of controls in the veterinary field.
• Please feel free to use your imaginations and both departments working together.
• Mr President, I wish to begin by welcoming the Commissioner's clear commitment to producing the new directive as soon as possible and by thanking him for outlining a number of important measures on which he and his departments are already working.
• Listen, we got the whole PR department working on this.
• Are we the only department working today?
• As for the directive on forest fires, my departments are working on a communication on disaster prevention, and one option to be assessed is to institute legislation specifically on forest fires.
• GD HAS NINE DEPARTMENTS WORKING ON THIS.
• I want him to see that we've got every department working on this.
• The day I was there, yesterday, there were around 1200 rescuers from the civil protection, environment, health and police departments working tirelessly on the ground.
• Fire department's working on getting them up and out.
• He was a member of my department, working undercover in Europe.
• I had a Joint Justice Department ATF working group looking into regulating 3D firearms.
• You think someone in the department's working with them?
• The u.s. state department Is working very closely with both the indian And pakistani armed forces to locate him.
• So the Health department is working on a poster campaign to warn people about diseases.
• Our department is working with the Office of Foreign Assets Control.
• disbanding the former Directorate-General for Research and re-establishing it in the form of policy departments working closely with parliamentary committees,

Some examples from the web:

• Ambassador Underwood and the State Department are working with all interested parties toward that end.
• I welcome the fact that Commissioner Patten and his department are working in this area.
• As the first point of this programme, my departments are working on an improvement of the Community system of controls in the veterinary field.
• Please feel free to use your imaginations and both departments working together.
• At which department are you actually working?
• Listen, we got the whole PR department working on this.
• Are we the only department working today?
• As for the directive on forest fires, my departments are working on a communication on disaster prevention, and one option to be assessed is to institute legislation specifically on forest fires.
• GD HAS NINE DEPARTMENTS WORKING ON THIS.
• I want him to see that we've got every department working on this.
• The day I was there, yesterday, there were around 1200 rescuers from the civil protection, environment, health and police departments working tirelessly on the ground.
• Fire department's working on getting them up and out.
• He was a member of my department, working undercover in Europe.
• I had a Joint Justice Department ATF working group looking into regulating 3D firearms.
• You think someone in the department's working with them?
• The u.s. state department Is working very closely with both the indian And pakistani armed forces to locate him.
• So the Health department is working on a poster campaign to warn people about diseases.
• Our department is working with the Office of Foreign Assets Control.
• disbanding the former Directorate-General for Research and re-establishing it in the form of policy departments working closely with parliamentary committees,
• OECD China's Financial Sector Reforms, Economic Department Working Paper No. 747, ECO/WKP (2010) 3, 1 February 2010, (see pages 2, 8-15, 36).