A Philadelphia woman was arrested on Friday on charges that she tried to join and martyr herself for the Islamic State, a day after two women in New York were charged with plotting to wage jihad by building a bomb and using it for a Boston Marathon-type attack.

Keonna Thomas, 30, was preparing to travel overseas to fight with the terror group and hoped to make it to Syria, authorities said. Instead, she was arrested at her home, which has three small US flags adorning the porch.

Authorities said that she communicated with an Isis fighter in Syria who asked if she wanted to be part of a martyrdom operation. She told the fighter that the opportunity “would be amazing”, according to the documents.

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It was unclear if she had a lawyer who could comment on the charges; a woman who answered the phone at her home declined to comment. Thomas was due to make an initial appearance in federal court on Friday afternoon.

The women in the New York case are accused of plotting to wage violent jihad by building a homemade bomb and using it for an attack like the 2013 Boston Marathon bombings, which were carried out from bombs that utilised pressure cookers. They were ordered held without bail after a brief court appearance Thursday. The lawyer for one of them said his client would plead not guilty.

Thomas is charged with providing material aid to terrorists, one of the same charges filed in 2010 against another Pennsylvania woman, Colleen LaRose, known as Jihad Jane, and two co-defendants in a terror plot that prosecutors say also involved online messages and recruitment for overseas terror suspects.

Authorities have said foreign terrorists seek US women because their western looks and American passports make it easier for them to travel overseas.

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Thomas’s posts in support of Isis started in August 2013, when she reposted a Twitter photograph of a boy holding weapons, authorities said. She called herself Fatayat Al Khilafah and YoungLioness and tweeted posts such as: “When you’re a mujahid, your death becomes a wedding”, according to the FBI affidavit filed in the case.

She soon began trying to raise money for the cause online and told a Somalia-based jihadi fighter from Minnesota that she soon hoped to have enough money to travel, authorities said.

She applied for a passport in February and bought a ticket to travel to Barcelona on 29 March, the affidavit said. Authorities would not immediately say why she had not made the trip.

Jihad Jane got a 10-year term in January for agreeing to kill Swedish artist Lars Vilks, who drew a cartoon that had offended Muslims, while a Colorado woman, Jamie Paulin-Ramirez, is serving eight years. Both women began their involvement online but ultimately traveled to Ireland to join a terror cell. Paulin-Ramirez brought her young son and married an Algerian terror suspect there.

An immigrant teen from Pakistan who met LaRose online when he was an honours student in suburban Baltimore was sentenced to five years.

The teen, Mohammad Hassan Khalid, never left home, but he opened a box LaRose had sent him that contained a passport and money, and sent some of the items to Ireland. He was arrested before he turned 18, becoming the rare juvenile in federal custody on a terrorism charge.

All three ultimately agreed to cooperate with authorities, shaving years off their sentences.