Turkey retaliated by halting visa services in the US for Americans traveling to Turkey. Reports say the man was accused of having ties to followers of the cleric blamed for 2016's failed coup.
According to the embassy, Ankara assured the US embassy that there were no additional local employees under investigation, that the local staff will not be detained or arrested for performing their official duties and that Turkish authorities will inform the USA government in advance if any local staff face detention.
USA authorities then sought assurances from top Turkish officials that no further staff members would be placed under investigation.
The announcements turn the page on a visa crisis triggered almost three months ago by the arrest of a staff member at the American mission in Ankara, but relations between the North Atlantic Treaty Organisation allies remain tense.
The Turkish embassy in Washington welcomed the United States decision and said visa restrictions for U.S. citizens imposed during the dispute would also be lifted.
The US in November said it has resumed limited visa services, a move matched by Turkey's missions in the US.
Ley Seguridad Interior es perfectible: Meade
El aspirante a la candidatura del PRI a la presidencia , José Meade , defendió la Ley de Seguridad Interior porque brinda certeza a los ciudadanos sobre cómo, con qué y por cuánto tiempo participarán las Fuerzas Armadas cuando se enfrenta un reto de inseguridad.
Turkey was pleased by the announcement but hit back regarding the statement issued by the USA, saying that it had provided no such assurances in relations to ongoing legal issues.
Ankara responded with an identical statement, imposing tit-for-tat travel restrictions, by issuing a statement through its embassy in Washington, saying, "Recent events have forced Turkish Government to reassess the commitment of the Government of the United States to the security of Turkish Mission facilities and personnel".
In March, a Turkish employee at the U.S. consulate in the southern city of Adana was also arrested on charges of supporting the outlawed Kurdistan Workers' Party (PKK).
Turkey has expressed concern over the arrest and trial of a Turkish banker Mehmet Hakan Atilla in the US.
Turkey has blamed Gulen, a US-based Muslim leader, of being behind a failed coup attempt past year, an accusation that Gulen has vehemently denied.
It further added that Turkey had serious concerns regarding the cases of Turkish nationals in the United States. "U.S. officials will continue to engage with their Turkish counterparts to seek a satisfactory resolution to these cases".